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If you’re planning to take the ATI TEAS Science exam, you’ll need to know a lot about human anatomy and physiology.

This in-depth guide will teach you everything you need to know! We’ll cover all the key topics on the exam, including cells, tissues, and organ systems; skeletal system; muscular system; nervous system; cardiovascular system; respiratory system; urinary system; and digestive system. Let’s get started!

Objectives for Human Anatomy and Physiology

Total scored items on ATI TEAS: 18 questions out of 44

Demonstrate Knowledge of the General Orientation of Human Anatomy

Anatomical Terminology

The ATI TEAS will expect you to be able to identify the position and location of the human body. Common anatomical terminology you may see is

  • Cephalic – head
  • Cranial- skull
  • Facial – face
  • Frontal – forehead
  • Occipital – base of the skull
  • Temporal – temple
  • Orbital or ocular – eye
  • Otic – ear
  • Buccal – cheek
  • Nasal – nose
  • Oral – mouth
  • Mental – chin
  • Cervical – neck
  • Sternal – breastbone
  • Thoracic – chest
  • Mammary- breast
  • Acromial – shoulder
  • Scapular – shoulder blade
  • Vertebral – spinal column
  • Lumbar – lower back
  • Dorsal – back
  • Axillary – Armpit
  • Brachial – Arm
  • Antecubital – front of the elbow
  • Olecranal or cubital – back of the elbow
  • Antebrachial – forearm
  • Carpal – wrist
  • Palmar – palm
  • Pollex – thumb
  • Dorsum – back of the hand
  • Manual – hand
  • Digital or phalangeal – fingers
  • Abdominal – abdomen
  • Umbilical – naval
  • Coxa – hip
  • Sacral – between the hips
  • Coccygeal – tailbone
  • Gluteal – buttock
  • Pelvic – pelvis
  • Pubic – pubis
  • Perineal – area between anus and external genitals
  • Inguinal – groin
  • Femoral – thigh
  • Patella – front of the knee
  • Popliteal – back of the knee
  • Crural – shin
  • Sural – calf
  • Pedal – foot
  • Tarsal – ankle
  • Digital of phalangeal – toe
  • Pedal – foot
  • Plantar – sole of the foot
  • Calcaneal – heel
  • Tarsal – ankle
  • Dorsum – top of the foot
  • Hallux – the great toe

Anatomical Position and Anatomical Direction

When studying human anatomy, it is important to use a standard anatomical position. This position includes the following:

  • Anterior (toward the front) – For example, the kneecap is on the anterior side of the leg.
  • Posterior (toward the back) – For example, the shoulder blades are located on the posterior side of the body.
  • Superior (toward the head) – For example, the hand is part of the superior extremity.
  • Inferior (toward the feet) – For example, the foot is part of the inferior extremity.
  • Medial (toward the midline) – For example, the chest is medial to the arm.
  • Lateral (away from the midline) – For example, the little toe is lateral to the big toe on the same foot.
  • Proximal (closer to the trunk of the body) – For example, the proximal end of the femur joins the pelvic bone.
  • Distal (farther from the trunk of the body) – For example, the hand is distal to the shoulder.

You will also need to be familiar with common directional terms, such as:

  • A sagittal plane or median is a vertical plane that divides the body into right and left halves.
  • A frontal plane or coronal is a vertical plane that divides the body into anterior (front) and posterior (back) halves.
  • A transverse plane or cross-section is a horizontal plane that divides the body into superior (upper) and inferior (lower) halves.

Describe the Anatomy and Physiology of the Respiratory Systems

Structure of the Respiratory System

The respiratory system is responsible for taking in oxygen from the environment and releasing carbon dioxide. The structure of the respiratory system includes the nose, mouth, throat, larynx, trachea, bronchi, and lungs.

  • The nose is the external opening of the respiratory system.
  • The nostrils lead into the nasal cavity, which is divided into two sections by the septum.
  • The mouth and throat are also part of the respiratory system.
  • The throat, or pharynx, is a tube that starts behind the nose and goes down to the esophagus.
  • The larynx, or voice box, is located at the top of the trachea.
  • The trachea, or windpipe, is a tube that goes from the larynx to the bronchi.
  • The bronchi are the two main tubes that lead from the trachea to the lungs.
  • The bronchioles are the smaller tubes that branch off from the bronchi and lead to the alveoli.
  • The alveoli are tiny sacs where gas exchange takes place. These are small, single-cell structures that group together in clusters like grapes.
  • The right lung is divided into three sections, while the left lung is divided into two sections. The left lung allows for more space to house the heart.

The Function of the Respiratory System

The respiratory system is responsible for taking in oxygen and releasing carbon dioxide.

When you breathe in, or inhale, your diaphragm contracts and moves downward. This increases the volume of your thoracic cavity and decreases the pressure inside of it. Oxygen is pulled in from the atmospheric air as well as other elements. Oxygen passes from the alveoli into the blood.

As a result, air flows into your lungs.

When you breathe out, or exhale, your diaphragm relaxes and moves upward. This decreases the volume of your thoracic cavity and increases the pressure inside of it. Carbon dioxide is released from the alveoli into the lungs also known as ventilation.

As a result, air flows out of your lungs.

The respiratory system is also responsible for maintaining the pH of the blood.

When the blood becomes too acidic, the respiratory system kicks in to remove the excess acid.

This is done by blowing off carbon dioxide, which is an acidic gas.

Factors that Affect the Respiratory System

There are a number of factors that can affect the respiratory system.

Diseases, such as pneumonia, bronchitis, and asthma, can all cause problems with breathing. Asthma is a common condition that causes the airways to narrow. Mucus buildup can occur making it difficult to inhale and exhale.

Smoking cigarettes is also a major factor that can damage the respiratory system.

Cigarette smoke contains a number of harmful chemicals that can damage the lungs and airways.

Other factors, such as pollution and dust, can also affect the respiratory system.

When the air quality is poor, it can irritate the lungs and cause problems with breathing.

Allergies and inflammation can also play a role in the respiratory system. If you have allergies, your airways may be inflamed, which can make it difficult to breathe. People may experience shortness of breath, wheezing, and difficulty breathing.

Describe the Anatomy and Physiology of the Cardiovascular Systems

Structure of the Cardiovascular System

The cardiovascular system is made up of the heart, blood vessels, and blood.

The heart is a muscular organ that pumps blood throughout the body.

  • The heart has four chambers: the right atrium, left atrium, right ventricle, and left ventricle.
  • The right atrium and left ventricle are on the right side of the heart, while the left atrium and right ventricle are on the left side.
  • The septum is a wall that separates the right and left sides of the heart.

The blood vessels are the tubes that carry blood throughout the body.

There are three major types of blood vessels: arteries, veins, and capillaries.

  • Arteries carry oxygen-rich (oxygenated) blood away from the heart, while veins carry oxygen-poor (deoxygenated) blood back to the heart.
  • Capillaries are tiny blood vessels that connect the arteries and veins.
  • Blood is a liquid that carries oxygen and nutrients to the cells of the body and carbon dioxide and wastes away from the cells.

The heart undergoes two cycles of contractions: the systole and the diastole.

  • The systole is the contraction of the heart, while the diastole is the relaxation of the heart.
  • During the systole, blood is pumped out of the heart and into the arteries. The atrioventricular (mitral and tricuspid) valves close causing the “lub” sound.
  • During the diastole, blood flows into the heart and fills the chambers. The semilunar (aortic and pulmonic) valves cause the “dub” sound.

The heart has its own electrical system that controls the heart rate.

The sinoatrial (SA) node is the pacemaker of the heart and sets the pace for the heart rate.

The electrical signal then travels through the atrioventricular (AV) node, bundle of His, and Purkinje fibers to the ventricles.

This causes the ventricles to contract and pump blood out of the heart.

Blood Flow Through the Cardiovascular System

The cardiovascular system is a closed system, meaning that the blood stays in the vessels and does not leak out under normal conditions.

The heart pumps oxygenated blood through the arteries from the lungs > left atrium > left ventricle > aorta of the body away from the heart.

The blood then flows through the capillaries, where oxygen and nutrients are exchanged in the tissues for carbon dioxide and wastes.

The carbon dioxide, wastes, and oxygen-poor (deoxygenated) blood are then transported through the veins back to the heart. The blood enters through the right atrium > right ventricle > lungs. Where the carbon dioxide is released for oxygen and the entire process starts over.

Functions of the Cardiovascular System

The cardiovascular system is responsible for delivering oxygen and nutrients to the cells of the body and removing carbon dioxide and wastes.

  • The heart pumps blood through the arteries to the cells of the body.
  • Oxygen and nutrients are delivered to the cells, and carbon dioxide and wastes are removed.

The cardiovascular system is also responsible for maintaining the body’s blood pressure.

  • Blood pressure is the force of the blood against the walls of the arteries.
  • If the blood pressure is too high, it can damage the arteries.
  • If the blood pressure is too low, it can cause problems with blood flow.

The cardiovascular system also helps to regulate the body’s temperature.

  • When the body temperature rises, the blood vessels dilate (widen) to allow heat to escape from the body.
  • When the body temperature drops, the blood vessels constrict (narrow) to prevent heat from escaping from the body.

The cardiovascular system is also responsible for maintaining the body’s pH.

  • A bicarbonate buffer system helps maintain acid by removing excess hydrogen ions from the blood.

The cardiovascular system is responsible for a variety of other functions, including:

  • Transporting hormones around the body
  • Helping to fight infections
  • Aiding in the digestion of food
  • Assisting in the repair of damaged tissue

Describe the Anatomy and Physiology of the Digestive System

Structure of the Digestive System

The digestive system is composed of the gastrointestinal (GI) tract and accessory organs.

The GI tract is a long, continuous tube that starts at the mouth and ends at the anus.

The GI tract is divided into the following parts: The mouth, esophagus, stomach, small intestine, large intestine, and rectum.

  • Digestion begins in the mouth where you chew and mechanical digestion (physical breakdown) of food occurs. Mucus in saliva lubricates the food and enzymes such as amylase and lipase initiate the chemical digestion of starches and lipids.
  • A bolus of food is swallowed and travels through the pharynx into the esophagus.
  • Peristalsis (contractions of muscles) occurs in the esophagus to move the food into the stomach.
  • The stomach is a J-shaped sac that stores food, initiates chemical digestion with enzymes, and mixes the food.
  • Gastric acid kills bacteria, denatures proteins, and activates digestive enzymes.
  • The small intestine is the main site of digestion and absorption. It is composed of the duodenum, jejunum, and ileum.
  • The small intestine is coiled and has a series of foldings that increase the surface area for absorption.
  • The large intestine is composed of the cecum, colon, and rectum.
  • The large intestine absorbs water, electrolytes, and vitamins produced by enteric bacteria.
  • The rectum is the final section of the GI tract and stores feces until they are eliminated through defecation.

The accessory organs include the teeth, tongue, salivary glands, liver, gallbladder, and pancreas.

These organs help to break down food into smaller pieces so that the body can absorb the nutrients.

Enzyme and Hormones Involved in Digestion

There are several hormones involved in the digestive process, including:

  • Gastrin: This hormone is produced by the stomach and stimulates the production of stomach acid.
  • Cholecystokinin (CCK): This hormone is produced by the small intestine and stimulates the release of enzymes from the pancreas and bile from the liver.
  • Secretin: This hormone is produced by the small intestine and stimulates the production of bicarbonate by the pancreas.
  • Insulin: This hormone is produced by the pancreas and helps to regulate blood sugar levels.
  • Glucagon: This hormone is produced by the pancreas and helps to release glucose from the liver.
  • Bile: This fluid is produced by the liver and stored in the gallbladder. Bile breaks down fats in the small intestine.

Describe the Anatomy and Physiology of the Nervous System

Divisions of the Nervous System

The nervous system can be divided into the central nervous system (CNS) and the peripheral nervous system (PNS).

  • The CNS is composed of the brain and the spinal cord. This is the central command center where all communication and actions occur in the body.
  • The PNS is composed of the nerves that branch off from the spinal cord and innervate the body. This system sends the signals by the brain to the targeted locations.
  • The nervous system is responsible for transmitting signals between the body and the brain.

Structure of the Neuron

The basic unit of the nervous system is the neuron. Neurons are composed of the cell body, dendrites, and an axon.

  • The cell body contains the nucleus and other organelles.
  • Dendrites are short, branch-like extensions that generated graded electrical impulses.
  • The axon is a long extension that transmits the signals to other neurons.
  • At the end of the axon are the terminal buttons which release neurotransmitters called the axon terminal.
  • Myelin sheath is a white, fatty substance that covers the axon and helps to increase the speed of nerve impulses.
  • Synapse is the space between the terminal buttons of one neuron and the dendrites of another neuron.

The Function of the Neuron

The nervous system is responsible for transmitting signals between the body and the brain. These signals can be in the form of electrical impulses or chemical signals.

The electrical impulses are generated by the movement of ions across the cell membrane. This action potential is then transmitted down the axon to the terminal buttons.

The chemical signals are transmitted by the release of neurotransmitters from the terminal buttons. These neurotransmitters bind to receptors on the dendrites of the next neuron and generate an electrical impulse.

This process allows for communication between different parts of the body and the brain.

The nervous system is responsible for transmitting signals between the body and the brain.

Sensory (afferent) neurons send messages to the central nervous system. Motor (efferent) neurons send messages to muscles and can be further divided into the autonomic (involuntary) and somatic (voluntary) nervous systems.

  • The autonomic nervous system is responsible for involuntary actions such as heart rate, digestion, and respiration.
  • The somatic nervous system is responsible for voluntary actions such as the movement of the limbs.

Describe the Anatomy and Physiology of the Muscular System

Types of Muscle Tissues

There are three types of muscle tissues in the body: skeletal, cardiac, and smooth.

  • Skeletal muscle is attached to bones and is responsible for the movement of the body. These muscles are striated and very strong. This muscle is the only voluntary tissue in the body. 
  • Cardiac muscle is found in the heart and pumps blood throughout the body. These muscles are also striated. Cardiac muscle tissue cannot be consciously controlled making the muscle involuntary.
  • Smooth muscle is found in the walls of internal organs such as the stomach, intestines, and blood vessels. These muscles are not striated and involuntary as they cannot be controlled consciously. These muscles are the weakest of all off muscle tissues.

The Function of Muscle Tissues

Muscles are responsible for the movement of the body. They generate force by contracting and produce movement by moving the bones to which they are attached. There are over 700 named muscles in the body and makeup approximately half of the total body weight.

Nerves Control Muscles In the Nervous System

Nerves control muscles by sending electrical impulses to the muscle. These impulses cause the muscle to contract and generate force. The nerve impulse originates in the brain and is sent through the spinal cord to the muscle.

The message is then sent down the axon of the nerve to the muscle. The muscle fibers receive the message and contract.

Describe the Anatomy and Physiology of the Male and Female Reproductive Systems

Structures of Male Reproductive System

The male reproductive system is made up of the testes, epididymis, vas deferens, seminal vesicles, prostate gland, and penis.

  • The testes are a pair of oval-shaped organs that produce sperm and testosterone.
  • The epididymis is a long, coiled tube that stores and transports sperm.
  • The vas deferens is a long, thin tube that carries sperm from the epididymis to the seminal vesicles.
  • The seminal vesicles are a pair of sac-like structures that produce a fluid that nourishes the sperm.
  • The prostate gland is a small, round organ that produces a fluid that helps to transport the sperm.
  • The penis is a long, cylindrical organ that carries urine and sperm out of the body.

Structures of Female Reproductive System

The female reproductive system is made up of the ovaries, fallopian tubes, uterus, vagina, and vulva.

  • The ovaries are a pair of small, oval-shaped organs that produce eggs and hormones.
  • The fallopian tubes are a pair of long, thin tubes that carry eggs from the ovaries to the uterus.
  • The uterus is a pear-shaped organ that houses and protects a developing fetus.
  • The vagina is a long, cylindrical organ that carries blood and mucosal tissue from the uterus during a women’s monthly period; provides a passageway for intercourse and sperm until it is distributed to the uterus; and also allows passage for vaginal childbirth.
  • The vulva is the external female genitalia that includes the labia, clitoris, and urethra.

Relationship between the Reproductive System and Endocrine System

There are various hormones that are part of the endocrine system that help control processes in the reproductive system. These include gonadotropin-releasing hormone, follicle-stimulating hormone, luteinizing hormone, testosterone, and estrogen.

  • Gonadotropin-releasing hormone is produced in the hypothalamus and stimulates the release of follicle-stimulating hormone and luteinizing hormone from the pituitary gland.
  • The follicle-stimulating hormone helps to stimulate the growth of eggs in the ovaries and control the menstrual cycle.
  • Luteinizing hormone helps to trigger ovulation, the release of an egg from the ovary.
  • Testosterone is a hormone produced by the testes that help to produce sperm and develop male characteristics. Unlike in females, sperm is not cyclical like eggs and are constantly produced and matured.
  • Estrogen is a hormone produced by the ovaries that helps to develop female characteristics and regulates the menstrual cycle.

In the female reproductive system, the FSH signals the ovaries to produce more estrogen. Estrogen causes an egg to mature. LH is released causing the egg to produce progesterone to prepare the endometrium for implantation. The egg is then released from the ovary and travels down the fallopian tube to the uterus. If the egg is fertilized by a sperm, it will implant in the uterus and begin to grow. If the egg is not fertilized, it will be shed during menstruation.

Describe the Anatomy and Physiology of the Integumentary

Structure of the Integumentary System

The integumentary system is made up of the skin, hair, nails, and sweat glands.

The skin is the largest organ in the body and is made up of three layers: the epidermis, dermis, and subcutaneous / hypodermis.

  • The epidermis is the outermost layer of skin that provides a waterproof barrier and protects the body from infection.
  • The dermis is the middle layer of skin that contains blood vessels, nerves, hair follicles, and sweat glands.
  • The subcutaneous / hypodermis is the innermost layer of skin that consists of fat and connective tissue.

Functions of Integumentary System

The integumentary system has several functions, including protection, regulation of body temperature, and sensation.

Protection: The skin protects the body from harmful substances, UV rays, and excessive water loss by creating a barrier from outside pathogens. Melanocytes produce melanin that helps protect against ultraviolet radiation.

Excretion: The sweat glands help to regulate body temperature by producing sweat that evaporates and cools the body. Sweat contains trace amounts of lactic acid, urea, and alcohol.

Sensation: The skin is packed with nerve endings that allow us to feel touch, pressure, heat, and cold.

Homeostasis and the Integumentary System

The integumentary system helps to maintain homeostasis by regulating body temperature and fluid balance.

When the body becomes too warm, the blood vessels in the skin dilate and sweat is produced to cool the body.

If the body becomes too cold, the blood vessels constrict and the body produces less sweat to maintain heat.

Describe the Anatomy and Physiology of the Endocrine System

Glands of the Endocrine System

The endocrine system is made up of a network of glands that produce and secrete hormones. These hormones help to regulate many body functions, including growth and development, metabolism, reproduction, and mood.

The pituitary gland is the master gland of the endocrine system and produces growth hormone, prolactin, and adrenocorticotropic hormone.

The thyroid gland produces thyroxine and calcitonin. Thyroxine helps to regulate metabolism, while calcitonin helps to regulate calcium levels in the blood.

The parathyroid gland produces parathyroid hormone, which helps to regulate calcium levels in the blood.

The thymus gland produces thymosin, which helps to develop the immune system.

The adrenal gland produces epinephrine and norepinephrine, which help to regulate the fight-or-flight response.

The pancreas produces insulin and glucagon, which help to regulate blood sugar levels.

The ovaries produce estrogen and progesterone, which help to regulate the menstrual cycle.

The testes produce testosterone, which helps to regulate the development of male reproductive organs and secondary sex characteristics.

Functions of the Endocrine System

The endocrine system regulates many body functions, including growth and development, metabolism, reproduction, and mood.

Growth and Development: Hormones play a role in regulating growth and development. For example, growth hormone helps to stimulate cell division and bone growth.

Metabolism: Hormones play a role in regulating metabolism. For example, insulin helps to regulate blood sugar levels.

Reproduction: Hormones play a role in reproduction. For example, estrogen and progesterone help to regulate the menstrual cycle.

Mood: Hormones play a role in mood. For example, norepinephrine and epinephrine help to regulate the fight-or-flight response.

Many hormones from the endocrine glands have different chemical structures including lipid-based hormones; nonpolar, fat-soluble hormones; and water-soluble hormones.

Lipid-based hormones are made of cholesterol and include testosterone and estrogen. These hormones are insoluble in water and are transported in the blood by carrier proteins.

Nonpolar, fat-soluble hormones are made of amino acids and include thyroid hormones. These hormones are insoluble in water and are transported in the blood by carrier proteins.

Water-soluble hormones are made of amino acids and include epinephrine. These hormones are soluble in water and are transported in the blood by diffusion.

Homeostasis and the Endocrine System

The endocrine system helps to maintain homeostasis by regulating growth and development, metabolism, reproduction, and mood.

For example, the endocrine system regulates growth and development by producing hormones that stimulate cell division and bone growth.

The endocrine system also regulates metabolism by producing hormones that help to regulate blood sugar levels.

In addition, the endocrine system regulates reproduction by producing hormones that help to regulate the menstrual cycle.

Finally, the endocrine system regulates mood by producing hormones that help to regulate the fight-or-flight response.

Positive and Negative Feedback Mechanisms

The endocrine system uses positive and negative feedback mechanisms to maintain homeostasis.

A positive feedback mechanism is a process that amplifies the change in a given direction.

For example, the release of oxytocin during childbirth is a positive feedback mechanism that amplifies the change in the given direction of childbirth. Oxytocin stimulates uterine contractions that cause the fetus to push against and stretch the cervix.

A negative feedback mechanism is a process that reverses the change or slows it down.

For example, the release of insulin in response to high blood sugar levels is a negative feedback mechanism that reverses the change or slows it down by lowering blood sugar levels. The pancreas is able to adjust the amount of hormone to secrete in proportion to the amount of blood glucose detected in the blood.

Describe the Anatomy and Physiology of the Urinary System

Structure of the Urinary System

The urinary system is made up of the kidneys, renal cortex, renal medulla, ureters, bladder, and urethra.

The kidneys are a pair of organs that filter blood and produce urine.

The renal cortex is the outer layer of the kidney that contains the renal pyramids and blood vessels. Erythropoietin is stimulated in the production of new red blood cells.

The renal medulla is the inner layer of the kidney that help to concentrate urine.

The ureters are a pair of tubes that carry urine from the kidneys to the bladder.

The bladder is a sac that stores urine until it is ready to be excreted.

The urethra is a tube that carries urine from the bladder to the outside of the body.

Function of the Urinary System

The urinary system is an integral part of homeostasis in the body. This system helps excrete waste and maintain balance.

The structural unit of the kidney is called the nephron. Nephrons are responsible for the filtration of blood by removing waste and reabsorbing water and molecules.

The glomerulus is a ball of capillaries that is the site of filtration in the nephron.

The tubule is a tube that leads from the glomerulus to the renal pelvis. The tubule is responsible for reabsorption and secretion.

What remains from the tubule is then carried into the kidney and drained from the ureter.

Relationship between the Cardiovascular System and Urinary System

The cardiovascular system and urinary system work together to maintain homeostasis in the body.

The cardiovascular system transports blood to the kidneys so that they can filter it.

The urinary system excretes waste and helps to regulate blood pressure by controlling the volume of blood.

In turn, the kidneys produce a hormone called erythropoietin that stimulates the production of new red blood cells in the cardiovascular system.

Describe the Anatomy and Physiology of the Immune System

Parts of the Immune System

The immune system is made up of innate defense and adaptive defense systems.

The innate defense system is the body’s first line of defense against infection and includes physical barriers, such as skin and mucous membranes, as well as chemical barriers, such as enzymes and stomach acid.

The adaptive defense system is the body’s second line of defense and includes the lymphatic system, white blood cells, and antibodies.

Function of the Immune System

The immune system protects the body from foreign invaders, such as bacteria, viruses, and fungi.

It does this by recognizing these invaders and producing antibodies to destroy them.

The immune system also helps to remove these invaders from the body and memory T cells help the body to remember these invaders so that they can be destroyed more quickly if they enter the body again.

Innate Immune System

The innate defense system is the body’s first line of defense against infection and includes physical barriers, such as skin and mucous membranes, as well as chemical barriers, such as enzymes and stomach acid.

One of the first responses is called the inflammatory response. This is when blood vessels dilate and white blood cells and fluids are sent to the area of infection.

Histamines are released causing an increase in blood flow to the area and the number of white blood cells called phagocytes. These phagocytes destroy the unknown bacteria.

This response helps to remove the foreign invader and to begin the healing process.

Adaptive Immune System

The adaptive defense system is the body’s second line of defense and includes the lymphatic system, white blood cells, and antibodies. This system functions with the help of antigens, antigen-presenting cells, helper T cells, cytotoxic T cells, cytokines, antibodies and memory cells.

Antigens are foreign invaders that the body had been exposed to, such as bacteria or viruses, that induce an immune response.

Antigen-presenting cells are white blood cells that engulf the foreign invader and present the antigen on its surface.

Helper T cells are a type of white blood cell that helps to activate the other cells of the immune system. The helper T cells induce B cells to secrete a large number of antibodies to bind to the antigen.

Cytotoxic T cells are a type of white blood cell that destroys infected cells.

Cytokines are chemicals that help to regulate the immune response and activate cytotoxic T cells.

Antibodies are proteins that attach to antigens and help to destroy them.

Memory cells are white blood cells that remember a specific foreign invader and help the body to respond more quickly if the invader enters the body again.

Passive vs Active Immunity

There are two types of immunity: passive and active.

Passive immunity is when the body is exposed to antibodies that have been made by another individual, such as when a mother passes antibodies to her child through breast milk.

Active immunity is when the body produces its own antibodies in response to an infection.

Active immunity is usually longer lasting than passive immunity.

Describe the Anatomy and Physiology of the Skeletal System

Structure and Function of the Skeletal System

The skeletal system is made up of bones, which are connected by joints. Bones are held together at the joints by ligaments.

Bones come in four major types: long, short, flat, and irregular.

Long bones are found in the arms and legs including the humerus, femur, ulna radius, tibia, and fibula. They are longer than they are wide and have a shaft with two enlarged ends, called the proximal and distal ends. The shaft of the long bone is called the diaphysis and the enlarged ends are called the epiphyses.

Short bones are found in the wrists and ankles and include the bones of the carpals and tarsals. They are approximately equal in length and width.

Flat bones are found in the ribs, sternum, shoulder blades, and hip bones. They are thin and often curved.

Irregular bones are found in the spine and include the vertebrae. They have a variety of shapes and are not symmetrical.

Bone Composition

Bones are made up of several different types of tissue including compact bone, spongy bone, cancellous bone, and trabecular bone.

Compact bone is the hard outer layer of bone that provides protection and support. It makes up the shaft of long bones and the flat surfaces of other bones.

Spongy bone is a porous, lightweight bone that is found at the ends of long bones and in the vertebrae.

Cancellous bone is a type of spongy bone that contains many small cavities.

Trabecular bone is a type of spongy bone that has a honeycomb-like structure.

Bones are also made up of marrow, which is a soft tissue that produces blood cells.

Brittle bone disease (osteogenesis imperfecta) results from a mutation in the gene that codes for collagen, which is a protein that makes up bone tissue. This disease causes bones to be fragile and break easily.

The Skeletal System and Muscular System

The muscular system provides movement for the skeletal system and they must work together through communication with the nervous system.

The muscle connects to bones with tendons which are comprised of connective tissue. For example, the biceps brachii is a muscle in the upper arm that attaches to the shoulder bone with tendons. The biceps brachii contract to lift the arm.

]]> ATI TEAS Science: Life and Physical Sciences – An In-Depth Guide https://nursecheung.com/teasscience-lifesciences/ Sat, 07 Jan 2023 17:15:08 +0000 https://nursecheung.com/ati-teas-science-life-and-physical-sciences-an-in-depth-guide/

Are you preparing to take the ATI TEAS Science Test?

If so, you will want to read this in-depth guide! We will provide an overview of the topics covered on the test, as well as some tips and strategies for success.

In this article, we will focus on the Life Sciences section.

Objectives for Life and Physical Science

Total scored items on ATI TEAS: 9 questions out of 44

Describe Cell Structure, Function, and Organization

Biological Hierarchy of the Body

When we discuss biological hierarchy, we are discussing the way we organize structures in living things by classifying structures from basic components to more complex components.

These structures are broken down into the following categories: chemicals, cells, tissues, organs, organ systems, and organisms.

Chemicals help build cells. Macromolecules are chemicals that are essential to life and are important in carbohydrates, proteins, lipids, and nucleic acids.

The cell is the basic unit of life. All living things are made up of cells. Cells perform all the functions necessary for life. There are more than 250 different types of cells that help the human body carry out life processes.

Tissues are made up of cells that have a similar structure and function. There are four types of tissues in the human body: epithelial, connective, muscle, and nervous. Tissues can help carry out functions such as protection, support, movement, and communication.

For example, the lungs deliver oxygen to the tissues via the bloodstream.

Organs are made up of tissues that work together to carry out a specific function. For example, the heart pumps blood through the body.

Organ systems are a group of organs that work together to carry out a specific function. The human body has 11 organ systems: the integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, and reproductive.

Each organ system has a specific function that helps the body carry out life processes. For example, the integumentary system helps protect the body from disease and infection.

Organisms are made up of one or more organ systems. Humans are multicellular organisms that are made up of 11 organ systems previously discussed.

Cell Structure and Function

Cells are the basic unit of life. All living things are made up of cells. Cells perform all the functions necessary for life. There are more than 250 different types of cells that help the human body carry out life processes.

The cell is composed of ten parts: the cell membrane, cytoplasm, Golgi Apparatus, lysosome, mitochondrion, nucleus, ribosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, and vacuole.

  • The cell membrane is a thin layer of protein and fat that surrounds the cell. The cell membrane is selectively permeable, meaning that it allows some substances to enter and exit the cell while keeping other substances out.
  • The cytoplasm is a jelly-like substance that contains the cell’s organelles. It helps support and suspends the structures inside the cell membrane. It can also transfer material required for other cellular processes.
  • The Golgi Apparatus is an organelle that helps to package and transport molecules within the cell. it also helps process proteins and lipid molecules.
  • Lysosomes are organelles that contain enzymes that break down food and other molecules. They aid in digestion and recycle old cell materials. Lastly, they destroy invading bacteria and viruses.
  • Mitochondria are organelles that produce energy for the cell. They convert nutrients into ATP, which is the cell’s energy source.
  • The nucleus is an organelle that contains the cell’s hereditary information also known as DNA. DNA is responsible for the cell’s growth, reproduction, and function.
  • Ribosomes are organelles that help synthesize proteins. Proteins are essential for the cell to carry out its functions. These organelles can be round on either the rough-endoplasmic reticulum or floating in the cytoplasm.
  • The rough endoplasmic reticulum is an organelle that helps to package and transport molecules within the cell. It is also involved in the synthesis of proteins.
  • The smooth endoplasmic reticulum is an organelle that helps to package and transport molecules specifically lipids within the cell but does not contain ribosomes. It is also involved in carbohydrate metabolism and inactivates toxins along with harmful metabolic products.
  • A vacuole is an organelle that stores food, water, and other materials. It also helps to maintain the cell’s shape.

Mitosis Process of the Cell Cycle

Mitosis is the process of cell division that results in two genetically identical daughter cells. The cell cycle is the sequence of events that a cell goes through as it grows and divides.

The cell cycle has four main stages: interphase, prophase, metaphase, anaphase, and telophase.

  1. Interphase is the first stage of the cell cycle. It is when the cell grows and carries out its normal functions. DNA starts to replicate.
  2. Prophase is the second stage of the cell cycle. In this stage, the chromosomes condense and become visible. The nuclear envelope also breaks down.
  3. Metaphase is the third stage of the cell cycle. In this stage, the chromosomes line up in the middle of the cell.
  4. Anaphase is the fourth stage of the cell cycle. In this stage, the chromosomes are pulled apart to opposite sides of the cell. Cell division begins.
  5. Telophase is the fifth and final stage of the cell cycle. In this stage, a new nuclear envelope forms around the chromosomes. The chromosomes uncoil and become less visible. The cell then divides into two daughter cells.

The cell cycle is a continuous process that takes place in all cells. Mitosis is just one part of the cell cycle. After telophase, the two daughter cells enter interphase and the cell cycle starts all over again.

Meiosis Process of the Cell Cycle

Cells can also divide through a process called meiosis. Meiosis is a type of cell division that results in four genetically diverse daughter cells.

Unlike mitosis, meiosis also has two main stages: meiosis I (interphase, prophase I, metaphase I, anaphase I, telophase I), and meiosis II (prophase II, metaphase II, anaphase II, and telophase II).

Interphase is the first stage of meiosis. The cell grows and carries out its normal functions. DNA starts to replicate.

Meiosis I

Prophase I is the second stage of meiosis. In this stage, the homologous chromosomes pair and start to crossover.

Metaphase I is the third stage of meiosis. In this stage, the homologous chromosomes line up in the middle of the cell in pairs.

Anaphase I is the fourth stage of meiosis. In this stage, the one chromosome from each homologous pair is pulled apart to opposite sides of the cell.

Telophase I is the fifth stage of meiosis. In this stage, the two daughter cells start to form. Each cell has half the number of chromosomes as the original cell. The cells also have a mixture of genetic information.

Meiosis II

Prophase II is the sixth stage of meiosis. In this stage, the daughter cells contain half of the chromosomes from the original cells.

Metaphase II is the seventh stage of meiosis. In this stage, the chromosomes line up in the middle of the cell again.

Anaphase II is the eighth stage of meiosis. In this stage, the sister chromatids are pulled apart to opposite sides of the cell.

Telophase II is the ninth and final stage of meiosis. In this stage, the cells divide into four genetically diverse daughter cells also known as haploids.

Meiosis is a continuous process that takes place in all cells. Meiosis I and II are just two parts of meiosis.

Describe the Relationship between Genetic Material and the Structure of Proteins

Chromosomes

Chromosomes are long, thread-like structures that are found in the nucleus of cells. They are made up of DNA and histone proteins. The winding structure condenses DNA and allows regulation.

All species of living things have chromosomes. Prokaryote organisms like bacteria have one chromosome. Eukaryote organisms have multiple chromosomes.

For example, humans have 46 chromosomes in every cell of their body, except for gametes or sex cells. Whereas dogs have 78 chromosomes.

Humans have 23 pairs of chromosomes. One pair is inherited from the mother and the other pair is inherited from the father. This makes up the diploid number.

Genes

Genes are the basic units of heredity. They are made up of DNA and are responsible for the characteristics of an organism. Genes are passed down from parent to offspring.

Each gene has the instructions for making a specific protein. Proteins are large molecules that perform many functions in the body.

It is estimated that the human body has 25,000 genes.

There are two types of genes: structural and regulatory genes.

  • Structural genes are responsible for the physical traits of an organism. For example, the color of your eyes or hair is determined by structural genes.
  • Regulatory genes control the activity of other genes. For example, regulatory genes can turn other genes on or off.

Deoxyribonucleic Acid (DNA)

DNA is the genetic material that contains genes that are coded with instructions to produce proteins in the cell. DNA is made up of two long chains of nucleotides that twist to create a double helix.

The sequence of the nucleotides in DNA determines the order of amino acids in proteins. This is known as the genetic code. These nucleotides have four bases: A (adenine), T (thymine), G (guanine), and C (cytosine).

A base pair is two nucleotides that are bonded together. For example, A pairs with T and G pairs with C. These complementary bases are liked by hydrogen bonds pair up to hold the two strands of DNA together.

The double helix structure of DNA is very important because it allows for replication. Replication is the process of making an identical copy of DNA.

A codon is a sequence of three nucleotides that code for a specific amino acid. There are 64 possible codons in the DNA code. 61 of these codons code for amino acids and the other three “stop signal” codons will end the gene.

A mutation may occur during replication that causes a permanent change in the DNA sequence. This can result in a change in the amino acid sequence of proteins and may lead to changes in the structure or function of the protein.

Ribonucleic Acids (RNA)

RNA’s principal role is to translate the genetic code of DNA into proteins.

RNA is very similar to DNA except for a few key differences. The most notable difference is that RNA is single-stranded. RNA also has the base uracil (U) instead of thymine (T).

Transcription and Translation

Transcription is the process of making RNA from DNA. The DNA double helix unwinds and one strand of the DNA serves as a template for RNA synthesis.

RNA polymerase is an enzyme that catalyzes the formation of RNA from nucleotides. This enzyme attaches to one end of the DNA template and then moves along the template, adding nucleotides one at a time.

As RNA is being made, it is complementary to the template strand of DNA. When RNA synthesis is complete, the RNA molecule is released from the DNA template, and the DNA double helix reforms.

RNA is found in three main forms: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA).

  • Messenger RNA (mRNA) is the RNA that carries the genetic code from the DNA in the nucleus to the ribosomes in the cytoplasm.
  • Transfer RNA (tRNA) is the RNA that helps to assemble amino acids into proteins that act as adapters in the translation of the genetic sequence.
  • Ribosomal RNA (rRNA) is the RNA that makes up ribosomes.

Translation is the process of making proteins from RNA. This occurs on ribosomes in the cytoplasm.

mRNA attaches to the small subunit of a ribosome and then tRNA brings amino acids to the ribosome. As the amino acids are brought to the ribosome, they are joined together by peptide bonds to form a protein.

The genetic code is read in groups of three nucleotides, called codons. Each codon codes for a specific amino acid.

The sequence of codons in mRNA determines the sequence of amino acids in a protein.

Apply Concepts Underlying
Mendel's Law of Inheritance

Dominant and Recessive Traits

Inheritance is the process by which traits are passed from parents to their offspring.

Mendel’s law of inheritance states that there are two alleles for each trait. Alleles are alternative forms of a gene.

One allele is dominant and the other allele is recessive. The allele that is expressed in the phenotype is the dominant allele.

Inheritance of Gene Paris

Each parent contributes one allele to their offspring. For example, if a mother has the allele for blue eyes (b) and the father has the allele for brown eyes (B), then their offspring will have the allele for blue eyes (b) and the allele for brown eyes (B).

The allele for blue eyes is recessive and the allele for brown eyes is dominant. This means that the phenotype of the offspring will be brown eyes.

However, if both parents have the allele for blue eyes (bb), then their offspring will also have the allele for blue eyes (bb) and the phenotype of the offspring will be blue eyes.

The combination of two alleles is called a genotype. If the chromosome contains two different alleles for a trait, then the genotype is heterozygous. If the chromosome contains two identical alleles for a trait, then the genotype is homozygous.

In the example above, the mother’s genotype is heterozygous (Bb) and the father’s genotype is heterozygous (Bb). The offspring’s genotype has a 25% chance of being homozygous (bb).

Using Punnett Squares

A Punnett square is a tool that is used to predict the genotypes and phenotypes of offspring.

To use a Punnett square, you need to know the genotypes of the parents.

In the Punnett square above, the mother’s genotype is represented by the letters “B” and “b” and the father’s genotype is represented by the letters “B” and “b”.

The genotypes of the offspring are represented by the letters “B” and “b”.

The phenotype of the offspring is represented by the color of the eyes.

As you can see, there is a 25% chance that the offspring will have blue eyes and a 75% chance that the offspring will have brown eyes.

Inheritance of Multiple Alleles or Dihybrid Cross

There are two alleles for each trait. However, there are more than two alleles for some traits.

For example, the allele for hair color can be black (B), brown (b), or blond (bl).

The allele for eye color can be blue (r), brown (R), or green (G).

A dihybrid cross is a Punnett square that shows the inheritance of two traits.

In the Punnett square above, the father’s genotype is represented by the letters “B”, “b”, and “bl” and the mother’s genotype is represented by the letters “B”, “b”, and “G”.

The genotypes of the offspring are represented by the letters “B”, “b”, “bl”, and “G”.

The phenotype of the offspring is represented by the color of the eyes and the color of the hair.

As you can see, there is a 25% chance that the offspring will have black hair and blue eyes, a 25% chance that the offspring will have black hair and brown eyes, a 25% chance that the offspring will have blond hair and blue eyes, and a 25% chance that the offspring will have blond hair and green eyes.

Non-Mendelian Inheritance

There are some exceptions to Mendel’s law of inheritance.

One example of non-Mendelian inheritance is incomplete dominance. In incomplete dominance, the phenotype of the offspring is a blend of the phenotypes of the parents.

For example, if a red flower (RR) is crossed with a white flower (WW), the offspring will be pink (RW).

Another example of non-Mendelian inheritance is codominance. In codominance, the phenotype of the offspring is a combination of the phenotypes of the parents.

For example, if a black chicken (BB) is crossed with a white chicken (WW), the offspring will be black and white (BW).

There are also some exceptions to Mendel’s law of independent assortment.

One example of this is linkage. Linkage is when two genes are located close to each other on the same chromosome and are inherited together.

Another example of this is sex-linked inheritance. Sex-linked inheritance is when a gene is located on the X or Y chromosome.

The most common example of this is color-blindness, which is caused by a gene located on the X chromosome.

Describe Structure and Function of Basic Macromolecules in the Biological System

Macromolecules

Macromolecules are large molecules that are essential for the structure and function of cells.

A polymer is a macromolecule that is made up of smaller units called covalent bond-linked monomers.

Chemical reactions can occur known as dehydration and hydrolysis.

  • Dehydration synthesis is the formation of larger molecules from smaller reactants accompanied by the loss of a water molecule.
  • Hydrolysis is the process of breaking down bonds to break monomers.

There are four major types of macromolecules: carbohydrates, lipids, proteins, and nucleic acids.

Carbohydrates

Carbohydrates are composed of carbon, hydrogen, and oxygen. They are also known as “sugars” or “starches” found in all living organisms.

They can be monosaccharides, disaccharides, or polysaccharides.

  • Monosaccharides are the simplest type of carbohydrate and they cannot be hydrolyzed to produce smaller units. A common monosaccharide is glucose.
  • Disaccharides are two monosaccharides that are joined by a covalent bond. A common disaccharide is sucrose (table sugar).
  • Polysaccharides are long chains of monosaccharides that are joined by covalent bonds. A common polysaccharide is starch and cellulose.

Carbohydrates can also take many different forms to perform functions. These forms can be linear, branched, and helix-shaped.

  • Linear carbohydrates are long unbranched chains of monosaccharides that form structures. For example, cellulose is a major component of rigid cell walls in plants.
  • Branched carbohydrates are shorter chains of monosaccharides with branches. For example, maltose is a common disaccharide found in germinating seeds that are used for energy storage.
  • Helix-shaped carbohydrates are coiled chains of monosaccharides that form structures. For example, DNA is a double helix-shaped nucleic acid.

Lipids

Lipids are composed of carbon, hydrogen, and oxygen. They are important energy storage, structural, and hormone macromolecules. Lipids are formed by a linear arrangement of carbon atoms and hydron atoms called fatty acid chains.

Lipids tend to be hydrophobic and nonpolar meaning they do not mix well with water.

Lipids can be divided into four groups: fat and oils, waxes, phospholipids, and steroids. All of these groups are insoluble in water.

  • A fat molecule is composed of a glycerol molecule and three fatty acid chains. Fats are used for long-term energy storage in the body. They are also useful in cushioning and insulating the human body.
  • Waxes are composed of a long chain of fatty acids that are linked to long-chain alcohol. Waxes serve as a protective coating on the surface of plants.
  • Phospholipids are composed of a glycerol molecule, two fatty acid chains, and a phosphate group. Phospholipids are a major component of cell membranes.
  • Steroids are composed of four interconnected carbon rings. Steroids include cholesterol, which is a structural component of cell membranes, and hormones like testosterone and estrogen. They are often used as chemical messengers.

Proteins

Proteins are composed of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. Proteins are made up of smaller units called amino acids that are linked together by peptide bonds.

Proteins can be classified into four groups: enzymes, structural proteins, storage proteins, and transport proteins.

  • Enzymes are proteins that catalyze biochemical reactions without being consumed by the reaction. They speed up reactions by lowering the energy required to initiate the reaction. These reactions can be exergonic (release energy) or endogenic (require energy).
  • Structural proteins provide support and structure.
  • Storage proteins store nutrients.
  • Transport proteins transport molecules.

Nucleic Acids

Nucleic acids are composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus. Nucleic acids store and transmit genetic information.

There are two types of nucleic acids: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) as we discussed previously.

Describe the Role of Micro-Organisms in Disease

Micro-Organisms

Micro-organisms, also known as microbes, are tiny living organisms. They are too small to be seen with the naked eye and can only be seen with a microscope.

Micro-organisms are found everywhere, including in the air, soil, water, and on plants and animals. Some micro-organisms can cause disease. Others are used in the production of food and drugs, or to help with the decomposition of organic matter.

The human body is home to many different types of micro-organisms, including bacteria, viruses, protozoans, fungi, and animals. Most of these micro-organisms are harmless and even helpful. For example, the bacteria in our gut help us to digest food.

However, some micro-organisms can cause disease. This can happen when they enter our bodies and multiply. It can also happen when the micro-organisms produce toxins that make us sick.

  • Bacteria are single-celled micro-organisms that can live in many different environments. Some bacteria cause diseases such as tuberculosis, meningitis, food poisoning, and more. Bacterial cells lack a nucleus making them prokaryotic in nature. Not all bacteria are pathogenic as many are harmless and help with body functions
  • Viruses are even smaller than bacteria and can only be seen with an electron microscope. They are not considered to be alive because they cannot reproduce on their own. Viruses must infect a host cell in order to reproduce. Examples include influenza, COVID-19, measles, mumps, and HIV.
  • Protozoans are single-celled micro-organisms that are found in water, soil, and air. They feed on other cells and divide based on their mode of movement (flagellar, ciliary, and amoeboid). Some protozoans cause diseases such as malaria, giardiasis, and amoebic dysentery.
  • Fungi are micro-organisms that are classified as eukaryotes (cells with a nucleus). They can be found in air, soil, water, and on plant and animal bodies. Some fungi are helpful, such as those used in the production of bread, cheese, and beer. Other fungi can cause diseases such as athlete’s foot, ringworm, and candidiasis.
  • Animals such as parasitic worms are large enough for people to see with the naked eye and can live on the body. Flatworms can live in the intestines and roundworms can live in the GI and lymphatic systems.

Infectious vs Non-Infectious Diseases

Infectious diseases can be spread from one person to another such as bacteria, viruses, protozoa, and fungi. They are commonly known as communicable diseases. Some examples include chickenpox, COVID-19, and cholera.

Noninfectious diseases are not caused by microorganisms and cannot be spread from person to person. They include cancer, heart disease, and diabetes.

How do Infectious Diseases Spread

Infectious diseases can spread through direct contact, indirect contact, or vectors.

  • Direct contact is when the infectious agent comes into contact with the mucous membranes or broken skin of another person. This can happen through shaking hands then touching your mucous membranes, kissing and broken skin present, or sexual contact.
  • Indirect contact is when an infectious agent comes into contact with an object or surface that another person will then touch. An example of this would be touching a doorknob that someone with the flu touched.
  • Vectors are living organisms that can carry and transmit an infectious agent to humans or other animals. The most common vectors are mosquitoes, ticks, and fleas.

Microscopes

A microscope is an instrument used to enlarge objects so they can be seen more clearly. There are two main types of microscopes used by microbiologists: light and electron microscopes.

Light microscopes are dependent on a light source. There are several types of light microscopes including dark-field, bright-field, phase contrast, fluorescence, differential interference contrast, and confocal scanning laser microscopes.

Electron microscopes are dependent on an electron beam. They are used to seeing objects at a much higher magnification than light microscopes (put to 150,000 times the size of the specimen). There are two types of electron microscopes: transmission (TEM) and scanning (SEM).

]]> ATI TEAS Science: Chemistry – An In-Depth Guide https://nursecheung.com/teasscience-chemistry/ Sat, 07 Jan 2023 17:15:05 +0000 https://nursecheung.com/ati-teas-science-chemistry-an-in-depth-guide/

The ATI TEAS Science exam is one of the most important tests that you will take to get into your academic career.

This test covers a variety of topics, including chemistry.

In this guide, we will provide an in-depth look at the chemistry section of the ATI TEAS Science exam.

We will discuss the types of questions that you will see on the test, and offer tips and strategies for how to best approach them.

Let’s get started!

Objectives for Chemistry

Total scored items on ATI TEAS: 8 questions out of 44

Recognize Basic Atomic Structure

Parts of an Atom

Atoms consist of structures within the nucleus containing protons and neutrons. Electrons orbit around the nucleus in shells.

A proton is a particle with a single positive charge, and a neutron is a particle with no electric charge.

An electron has a negative charge and is about 2000 times smaller than a proton.

The types of elements are determined by the number of protons within the nucleus. For example, carbon has 6 protons.

Isotopes are atoms of the same element that have a different number of neutrons.

For example, Carbon-12 and Carbon-14 are isotopes of carbon.

The atomic mass of an atom is the total number of protons and neutrons. As electrons are small their mass does not add to the mass of an atom.

The atomic mass is determined by adding the protons and neutrons together. For example, the atomic mass of Carbon-12 is 12 (the number of 6 protons + the number of 6 neutrons).

The atomic number is the number of protons in an atom.

Lastly, atoms can be positively charged, negatively charged, or neutral. This is determined by the number of protons in an atom.

If there are more electrons than protons, the atom will have a negative charge.

If there are more protons than electrons, the atom will have a positive charge.

If the number of protons and electrons are equal, then the atom is neutral.

Ions

Ions are atoms that have gained or lost protons, and as a result, have a charge either positive or negative. For example, traditionally sodium is made up of 11 protons, 12 neutrons, and 11 electrons. When sodium (Na) loses its one valence electron in its outermost shell, it becomes a cation with a charge of +.

  • Cations are atoms that have lost one or more electrons and have a resulting positive charge.
  • Anions are atoms that have gained one or more electrons and have a resulting negative charge.

When an atom gains electrons, it usually happens in the outermost shell.

For example, chlorine (Cl) has 17 protons, 18 neutrons, and 17 electrons. When chlorine (Cl) gains an electron, it becomes an anion with a charge of – .

Periodic Table of Elements

The periodic table of elements is a chart that shows how elements are related to one another.

The elements are organized by increasing atomic number. The columns of the periodic table are called groups, and the rows are called periods.

There are a few elements that do not fit perfectly into the periodic table. These are called transition elements or metalloids.

The first two rows of the periodic table (the alkali and alkaline earth metals) are considered the active metals.

The middle of the periodic table (the transition elements) are considered the reactive metals.

The elements in the far right column of the periodic table (the noble gases) are considered the inactive gases.

The types of elements are determined by the number of protons within the nucleus. The groups on the periodic table represent how many valence electrons are in an atom.

The columns on the periodic table go from left to right in order of increasing atomic number. The first column (group one) has one valence electron. The second column (group two) has two valence electrons, and so on.

The rows go from top to bottom in order of increasing atomic number. The first row (period one) has two valence electrons. The second row (period two) has eight valence electrons, and so on.

To identify the number of electrons and protons of an element, you must look at the integer shown on the periodic table. The integer is the element’s atomic number (which is shown as whole number without a decimal).

Atomic masses on the periodic table are shown as a decimal to account for the element’s various isotopes.

Orbitals are areas where electrons are likely to be found and are different to accommodate the different electron numbers.

  • The s orbital is a spherical area surrounding the nucleus. This orbital has a max of two electrons at a time.
  • The p orbital is a dumbbell-shaped area surrounding the nucleus. This orbital has a max of six electrons at a time.
  • The d orbital is an hourglass-shaped area surrounding the nucleus. This orbital has a max of ten electrons at a time.
  • The f orbital is an irregularly-shaped area surrounding the nucleus. This orbital has a max of fourteen electrons at a time.

The number of orbitals an element has is the same as the period number it’s in on the periodic table.

  • The first period has one orbital, the second period has two orbitals, and so on.
  • The orbitals are filled in order of increasing energy. The s orbital is always filled first, then the p orbital, and so on.

Valence electrons located in the outermost shell of an atom readily participate in chemical reactions. Elements are the most stable when they have a full valence shell.

Elements such as helium have full valence shells and are quite stable.

Other elements, such as sodium, have only one valence electron. These types of atoms are less stable and readily give up their valence electrons to achieve stability.

Ionic bonds are formed when atoms trade electrons in order to achieve stability. For example, when sodium (Na) and chlorine (Cl) form an ionic bond, Na gives up its one valence electron to Cl.

Covalent bonds are formed when atoms share electrons in order to achieve stability. For example, when two hydrogen (H) atoms form a covalent bond, they share their one valence electron.

In order to determine if a bond is ionic, covalent, or compound, you must look at the electronegativity of the atoms involved.

The electronegativity of an atom is a measure of how strongly it attracts electrons to itself.

The higher the electronegativity, the greater the atom’s attraction for electrons.

Atoms with high electronegativities (such as Cl) tend to form ionic bonds. Atoms with low electronegativities (such as H) tend to form covalent bonds.

Physical Properties and Changes of Matter

Physical Properties of Matter: Mass, Volume, and Density

Matter is anything that has mass and occupies space. Physical properties refer to the different properties of a substance that can change their state without changing the identity of the substance.

For example, water can exist in three states: solid, liquid, or gas. The states of matter are determined by the physical properties of the substance.

Mass is the amount of matter in an object. It is a measure of the inertia of an object and is measured in grams (g). For example, a paperclip has a mass of about 0.01 g.

Volume is the amount of space an object occupies and is measured in liters (L).

Density is the mass of an object divided by its volume. It is a measure of how much matter is packed into a given space and is measured in grams per liter (g/L).

The density of a substance can be affected by its temperature. For example, water has a density of 1000 kg/m^ at room temperature.

However, when water is heated, its density decreases and it expands.

When a substance changes state, its physical properties also change.

States of Matter

The most common states of matter are solid, liquid, gas, and plasma.

Solids have a definite shape and volume. They are the least compressible state of matter as molecules are packed together in a tight pattern.

Liquids have a definite volume but take the shape of their container. They are more compressible than solids as molecules are not packed together as tightly.

Gases have neither a definite shape nor volume. They are the most compressible state of matter as molecules are far apart from each other.

Plasma is a state of matter that is often found in the stars. It is a gas that is ionized, meaning that electrons have been stripped from the atoms.

The phase of a substance is dependent on two conditions: temperature and pressure.

Temperature is a measure of the average kinetic energy of the molecules in a substance. The higher the temperature, the more energy the molecules have (move particles of matter apart) and the more space they take up.

Pressure is a measure of the force exerted on an object by the surrounding atmosphere. The higher the pressure, the more the molecules are forced together.

The physical properties of a substance can be affected by changes in temperature and pressure. For example, water can exist in three states: solid, liquid, or gas. The state of water is determined by the temperature and pressure.

If the temperature is increased, the molecules of water will move faster and take up more space. This will cause the water to change from a solid to a liquid.

If the temperature is decreased, the molecules of water will move slower and take up less space. This will cause the water to change from a liquid to a solid.

If the pressure is increased, the molecules of water will be forced closer together. This will cause the water to change from a gas to a liquid.

If the pressure is decreased, the molecules of water will be forced further apart. This will cause the water to change from a liquid to a gas.

Changes Between States of Matter

Chemical properties of matter refer to the ability of a substance to change its identity. This can happen when the substance undergoes a chemical reaction.

These changes can include condensation, evaporation, sublimation, deposition, melting, and freezing.

  • Condensation is the process of a gas changing to a liquid. This happens when the molecules of the gas slow down and become closer together.
  • Evaporation is the process of a liquid changing to a gas. This happens when the molecules of the liquid gain enough energy to break away from the surface of the liquid.
  • Sublimation is the process of a solid changing to a gas. This happens when the molecules of the solid gain enough energy to break away from the surface of the solid.
  • Deposition is the process of a gas changing to a solid. This happens when the molecules of the gas slow down and become closer together.
  • Melting is the process of a solid changing to a liquid. This happens when the molecules of the solid gain enough energy to break away from each other.
  • Freezing is the process of a liquid changing to a solid. This happens when the molecules of the liquid lose enough energy to stay together.

The changes between states of matter are reversible. This means that the process can be reversed and the substance will change back to its original state.

For example, water can be evaporated and then condensed back to a liquid. Or, a substance can be melted and then frozen back to a solid.

Describe Chemical Reactions

Valence Electrons

In order to understand chemical reactions, it is important to know about valence electrons. Valence electrons are the electrons in the outermost energy level of an atom.

They are the electrons that are involved in chemical reactions. The number of valence electrons in an atom determines how it will react with other atoms.

Atoms can gain or lose valence electrons in order to achieve a full outer energy level. When this happens, the atom will form a chemical bond with another atom.

For example, when two chlorine atoms form a bond, each atom will have gained one valence electron. This is because chlorine has seven valence electrons.

Ionic and Covalent Bonds

There are two types of chemical bonds: ionic and covalent.

Ionic bonds are formed when atoms gain or lose valence electrons (take or giveaway).

Covalent bonds are formed when atoms share valence electrons.

Ionic bonds are usually formed between a metal and a non-metal. For example, sodium (Na) and chlorine (Cl) form an ionic bond.

Covalent bonds are usually formed between two non-metals. For example, carbon (C) and oxygen (O) form a covalent bond.

Chemical Reactions

Chemical reactions can be represented by chemical equations. Chemical equations are written using symbols and formulas. The symbols represent the elements in the reaction.

The formulas represent the compounds in the reaction (Reactants -> Products).

  • The reactants are the substances that are involved in the reaction.
  • The products are the new substances that are formed by the reaction.

For example, lets take a look at a combustion reaction.

Combustion is a type of reaction that happens when a substance reacts with oxygen (O) to form carbon dioxide (CO) and water (H).

The chemical equation for this reaction is:

C₆H₁₂O₆ (sugar) + 6O₂ (oxygen) -> 6CO₂ (carbon dioxide) + 2H₂O (water)

In this equation, C represents the element carbon, O represents the element oxygen, C₆H₁₂O₆ represents the compound sugar, 6O₂ represent the compound of oxygen, 6CO₂ represents the compound of carbon dioxide and 2H₂O represents the compound water.

The arrow in the equation means “reacts to form”. So, in this equation, the reactants are carbon and oxygen. The products are carbon dioxide and water.

Balancing Chemical Reactions

A chemical equation must be balanced. This means that there must be the same number of atoms of each element on both sides of the arrow.

For example, the equation for the combustion of methane (CH) is: CH₄ + 2O₂ -> CO₂ + 2H₂O

In order to balance this equation, we need to add a coefficient in front of each compound.

A coefficient is a number that is placed in front of a symbol or formula in order to multiply it.

Another example of balancing chemical reactions is the decomposition of water:

H₂O -> H₂ + O₂

In order to balance this equation, we need to add a coefficient of two in front of H₂O and H₂.

This is because there are two atoms of hydrogen (H) on the left side of the equation and two atoms of oxygen (O) on the right side of the equation.

Now that the equation is balanced, it looks like this:

2H₂O -> 2H₂ + O₂

Moles in Chemical Reactions

The mole is a unit that is used to measure the amount of a substance.

The mole can be used to measure the number of atoms, the number of molecules, or the mass of a substance.

The mole is used in chemical reactions because it allows us to calculate the amount of each substance that is needed in order to complete the reaction.

For example, lets say we want to know how many moles of oxygen we need in order to react with one mole of methane.

The equation for the combustion of methane is: CH₄ + O₂ -> CO₂ + H₂O

In this equation, we can see that for every one mole of methane (CH₄), we need one mole of oxygen (O₂).

This is because there are four atoms of carbon (C) in methane (CH₄) and for every one atom of carbon, we need two atoms of oxygen.

So, in order to react with one mole of methane, we need two moles of oxygen.

Demonstrate How Conditions Affect Chemical Reactions

Factors that Influence Reaction Rates

The rate of a chemical reaction is the speed at which the reactants are converted into products. Catalysts will speed up the reaction.

There are several factors that can influence the rate of a chemical reaction including endothermic reactions and exothermic reactions.

Endothermic reactions are reactions that absorb heat. The factor that influences the rate of endothermic reactions is the temperature.

  • Higher temperatures will increase the rate of reaction because it provides the energy that is needed for the reaction to occur.

Exothermic reactions are reactions that release heat. The factor that influences the rate of exothermic reactions is the concentration of the reactants.

  • Higher concentrations will increase the rate of reaction because there is a greater chance that the molecules will collide.

Chemical Equilibria

A chemical reaction is said to be at equilibrium when the rate of the forward reaction is equal to the rate of the reverse reaction.

At equilibrium, the concentrations of the reactants and products remain constant.

There are two types of equilibrium: dynamic equilibrium and static equilibrium.

  • Dynamic equilibrium is when the forward and reverse reactions are occurring at the same time.
  • Static equilibrium is when the concentrations of the reactants and products are not changing.

The position of equilibrium can be shifted by adding or removing reactants or products.

  • If you add reactants, the position of equilibrium will shift to the right.
  • If you remove reactants, the position of equilibrium will shift to the left.

Catalysts

A catalyst is a substance that increases the rate of a chemical reaction without being used up in the reaction.

Activation energy is the minimum amount of energy that is needed for a chemical reaction to occur.

Catalysts lower the activation energy by providing an alternative pathway for the reaction to occur.

For example, Enzymes are proteins that act as catalysts in biochemical reactions.

Enzymes are specific to the reaction that they catalyze and are usually named after the substrate that they act on.

Amylase is a enzyme catalyst that breaks down starch polymers and glucose monomers.

Understand Properties of Solutions

Polarity of Water

Water is a polar molecule. This means that the water molecules have a slight negative charge at the oxygen atom and a slight positive charge at the hydrogen atoms.

The polarity of water allows it to form hydrogen bonds with other molecules.

Hydrogen bonds are weak attractions between molecules.

Cohesion is the process of similar molecule surrounding and binding to another molecule.

  • Water molecules can surround and bind to other molecules because of the polarity of water. Water attracts water.

Adhesion is the process of dissimilar molecules binding to another molecule.

  • Water molecules can bind to other molecules because of the polarity of water. Water is consider the universal solvent, meaning there are many substances that can dissolve in water.

Solvents and Solutes

A solvent is a substance that dissolves in another substance.

  • Water is the most universal solvent.

A solute is a substance that dissolves in a solvent.

  • Sugar is the most common solute.

For example, a solution is formed when liquid mixes contains one or more solutes dissolve in a solvent.

Solutes can be classified as hydrophilic (water-loving) and hydrophobic (water-fearing).

An example of hydrophilic is salt and an example of hydrophobic is oil.

Solubility is the ability of a solute to dissolve in a solvent. The amount of solute that can dissolve in a given amount of solvent is called the solubility limit.

The solubility limit is dependent on the temperature.

For example, hot water can dissolve more sugar than cold water.

Concentration and Dilution of Solutions

The concentration of a solution is the amount of solute that is dissolved in a given amount of solvent.

Dilution is the process of adding solvent to a solution to decrease the concentration of the solution.

Different units of measure are used to express concentration of solutions depending on the application. The most common is molarity.

Molarity is a unit of measurement that describes the concentration of a solute in a solution. Molarity is expressed as moles of solute per liter of solution (mole of solute / liters of solution – mol/L).

Osmosis and Diffusion

Osmosis is the process of water molecules moving from an area of high water concentration to an area of low water concentration through a semi-permeable membrane.

A semi-permeable membrane is a barrier that allows some molecules to pass through but not others.

Diffusion is the process of molecules moving from an area of high concentration to an area of low concentration.

Osmosis and diffusion are both passive transport processes.

Passive transport processes do not require energy, they only require that the molecules be in motion.

An example of osmosis is when a plant takes in water from the soil through its roots.

An example of diffusion is when perfume molecules spread through a room.

Active transport is the process of molecules moving from an area of low concentration to an area of high concentration.

Active transport processes require energy because the molecules are moving against the concentration gradient.

An example of active transport is when a cell takes in glucose from the blood.

Describe Concepts of Acid and Bases

What are Acids and Bases?

An acid is a molecule that increases the concentration of hydrogen ions in a solution.

A base is a molecule that decreases the concentration of hydrogen ions in a solution.

pH

The strength of an acid or base is measured by the pH scale.

The pH scale ranges from 0 to 14.

A pH of 0 is the most acidic, a pH of 14 is the most basic, and a pH of 7 is neutral.

pH is a unit of measurement that describes the concentration of hydrogen ions in a solution.

The higher the concentration of hydrogen ions, the more acidic the solution.

The lower the concentration of hydrogen ions, the more basic the solution.

Buffers

A buffer is a solution that can resist changes in pH.

Buffers are important because they help maintain the pH of a solution within a certain range.

An example of a buffer is blood.

Blood has a pH of around 7.35 to 7.45, which is maintained by the buffer system.

The buffer system is made up of carbonic acid and bicarbonate.

  • Carbonic acid is weak acid and bicarbonate is a weak base.

Together, they help maintain the pH of blood within a certain range.

Neutralization Reactions

A neutralization reaction is a chemical reaction between an acid and a base.

The products of a neutralization reaction are water and salt.

Neutralization reactions are important because they help maintain the pH of a solution within a certain range.

An example of a neutralization reaction is the reaction between stomach acid and antacid.

Stomach acid has a pH of around 0.75, which is too low.

Antacid has a pH of around 11, which is too high.

When stomach acid and antacid react, they neutralize each other and the pH of the solution is brought to a more neutral value.

]]> ATI TEAS Science: Scientific Reasoning – An In-Depth Guide https://nursecheung.com/teasscience-scientificreasoning/ Sat, 07 Jan 2023 17:15:03 +0000 https://nursecheung.com/ati-teas-science-scientific-reasoning-an-in-depth-guide/

The ATI TEAS Science section is one of the most challenging for many test-takers. This is largely due to the fact that it covers scientific reasoning, which can be difficult to understand if you’re not familiar with the topic.

In this guide, we will break down scientific reasoning and discuss some strategies that you can use to answer the questions in the ATI TEAS Science section.

We’ll also provide a few practice questions so you can see how these concepts work in action.

Objectives for Scientific Reasoning

Total scored items on ATI TEAS: 9 questions out of 44

Basic Scientific Measurements and Measurement Tools

Units of Measurement

Scientists utilize the metric system to measure and record their findings. The metric system is based on the International System of Units, which uses the following units:

  • Length/distance: meter (m)
  • Mass: kilogram (kg)
  • Volume: liters (L)

Dimensional analysis is used to convert from one unit of measurement to another. This is often done by using a conversion factor, which is a ratio that compares two different units of measurement.

For example, if you want to convert from meters to centimeters, you would use the following conversion factor:

  •  length in centimeters = length in meters x 100

To use this conversion factor, you would set up the equation as follows:

  • length in centimeters (unknown) = length in meters (given) x 100

You would then solve for the unknown, which in this case is the length in centimeters.

Another example, if you want to convert liters to milliliters, you would use the following conversion factor:

  • volume in milliliters = volume in liters x 1000

You would set up this equation as follows:

  • volume in milliliters (unknown) = volume in liters (given) x 1000

As you can see, conversion factors are simply ratios that compare two different units of measurement.

Selecting a Measurement Tool

When scientists are conducting experiments, they must choose the appropriate measurement tool for the task at hand.

For example, if they need to measure the length of an object, they would use a ruler, meter stick, or a tape measure. Length is the distance from one end to another end of an object.

If they need to measure the volume of a liquid, they would use a graduated cylinder or volumetric pipette. Volume is measured by the amount of space an object takes up.

And if they need to measure the mass of an object, they would use a balance. Mass is measured by the amount of matter in an object.

It’s important to choose the right measurement tool for the job because using the wrong tool can lead to inaccurate results.

Choosing an Appropriate Scale of Measurement

In addition to choosing the right measurement tool, scientists must also choose an appropriate scale of measurement.

For example, if the mass of an object is very large it will likely be measured in kilograms very grams to be more efficient.

But if the object being measured is very small, such as a dust particle, it might be necessary to use milligrams or micrograms.

The same is true for length and distance. If the object being measured is very large, such as a building, it might be necessary to use kilometers or miles.

But if the object being measured is very small, such as a molecule, it might be necessary to use nanometers or picometers.

Again, it’s important to use the appropriate scale of measurement to ensure accuracy.

Apply Logic and Evidence to a Scientific Explanation

Drawing Conclusions

Empirical evidence is information that is gathered through observation and experimentation.

This type of evidence can be qualitative, which means it can be described in terms of quality or characteristics, or quantitative, which means it can be described in terms of quantity or amount.

In order to have confidence in the data that scientists collect, experiments are repeated with the same variables and procedures as previously performed.

When the results of these experiments are consistent with each other, they are said to be reproducible.

If the results of an experiment cannot be reproduced, this indicates that there is something wrong with the experiment and it must be repeated.

For example, consider a scientist is trying to determine the effect of a new drug on patients with a certain disease.

The scientist gives the drug to a group of patients and observes them over time.

The scientist then compares the results to a control group of patients who did not receive the drug.

If the results of this experiment cannot be reproduced, it means that the drug might not be effective.

Therefore, the scientist would need to repeat the experiment with a new group of patients to see if the results are reproducible.

If the results are still not reproducible, this would indicate that the drug is not effective and should not be used.

In order to make confident conclusions about the results of an experiment, scientists must use empirical evidence.

Identifying Cause and Effect Relationships

A cause is something that produces an effect and an effect is the result of a cause.

In order for scientists to identify a cause-and-effect relationship, they must use empirical evidence.

Consider the previous example of a scientist trying to determine the effect of a new drug on patients with a certain disease. The scientist would be to identify if the effect of the medication is working on the specific disease.

Evaluating Evidence

When scientists are evaluating evidence, they are looking at whether or not the evidence is reliable and valid.

Reliable evidence is information that can be trusted and is consistent.

Valid evidence is information that accurately represents what it is supposed to represent.

In order to determine if the evidence is reliable and valid, scientists must use a process for analyzing data that is free from bias. They avoid this by experimenting with placebo groups.

A placebo is a harmless substance that has no therapeutic effect.

By using placebo groups, scientists can be sure that any effects seen are due to the drug and not due to other factors.

Scientists also rely on independent variables and controlled variables.

An independent variable is a variable that is being tested and is not affected by other variables.

A controlled variable is a variable that is not being tested and is held constant.

For example, a scientist might be testing the effect of a new drug on patients with a certain disease.

The independent variable would be the new drug and the controlled variables would be the disease and the patients.

By keeping the controlled variables constant, scientists can be sure that any changes seen are due to the independent variable.

Predicting Relationship among Events, Objects, and Processes

Comparing Magnitude

When scientists are trying to determine the relationship among events, objects, and processes, they often use evidence from experiments to make predictions.

In order to make predictions, scientists must be able to compare the magnitude (size) of the evidence.

For example, the diameter of human hair can be measured in micrometers whereas the height of a human may be measured in meters.

It is important to understand the concept of scale when comparing the magnitude of evidence.

Determining Casual Relationships and Sequence of Events

Casual relationships are difficult to determine. As we know a cause is something that produces an effect and an effect is the result of a cause.

In order for scientists to identify a cause-and-effect relationship, they must use empirical evidence between the two variables.

Examples can include high blood pressure and vascular disease.

Determining a casual relationship could involve identifying the sequence of events that leads to a consequence.

For example, a sequence of events may include the process of body temperature increases and the breakdown of glycogen in the liver.

The sequence of events would be as follows:

First, the body temperature increases.

Second, the brain alerts the sweat glands to begin sweating.

Apply the Scientific Method to interpret a Scientific investigation

Identify a Relevant Hypothesis Based on a Given investigation

The scientific method is a process that scientists use to answer questions about the world around them.

The steps of the scientific method are as follows:

  1. First, identify a problem or question.
  2. Second, gather information about the problem or question.
  3. Third, form a hypothesis, which is a possible answer to the problem or question.
  4. Fourth, design and conduct an experiment to test the hypothesis.
  5. Fifth, analyze the data from the experiment and draw conclusions.
  6. Sixth, communicate the results of the experiment.

The scientific method is an important tool that scientists use to interpret scientific investigations.

A relevant hypothesis is a hypothesis that is based on the information given in an investigation.

For example, if a scientist is investigating the effect of a new drug on patients with a certain disease, the relevant hypothesis would be that the new drug will cure the disease.

Another example of a hypothesis may be that a new diet will help people lose weight.

Describe a Simple Experimental Design to Test a Hypothesis

A scientific hypothesis is a prediction of may occur during an experiment based on previously gathered background research. The experiment must be conducted to identify if the hypothesis is accurate and valid.

For example, an experiment may be conducted to identify the effect of sugary drinks and their relationship to obesity.

The independent variable would be the sugary drinks and the dependent variable would be obesity.

The control group would be given carbonated water to drink and the experimental group would be given sugary drinks.

Both groups would be monitored to see if there is a difference in weight gain.

The results of the experiment would help to validate or invalidate the hypothesis.

A simple experimental design to test a hypothesis should include an independent variable, a dependent variable, and a control group.

Another important aspect may be to consider the size of each experimental group.

If the sample size is too small, the results of the experiment may not be accurate.

It is important to carefully design an experiment in order to obtain accurate and reliable results.

Identifying Dependent Variables, Independent Variables, and Experimental Controls

When conducting an experiment, it is important to identify the dependent variable, independent variable, and experimental controls.

The dependent variable is the variable that is being measured in the experiment.

The independent variable is the variable that is being manipulated in the experiment.

The experimental controls are the conditions that are kept the same in the experiment.

For example, if a scientist is investigating the effect of 8 hours of sleep helping people be more alert.

The dependent variable would be alertness, the independent variable would be sleep, and the experimental control would be to keep all other conditions the same.

Determine Whether Experimental Results or Modules Support or Contradict a Hypothesis, Prediction, or Conclusion

The results of an experiment may support or contradict a hypothesis, prediction, or conclusion.

For example, if the hypothesis is that a new drug will cure a disease, the results of the experiment may support or contradict this hypothesis.

If the experimental results show that the new drug does indeed cure the disease, then the hypothesis is supported.

However, if the experimental results show that the new drug does not cure the disease, then the hypothesis is contradicted.

It is important for scientists to carefully analyze the results of an experiment in order to determine whether the hypothesis, prediction, or conclusion is supported or contradicted.

In some cases, the results of an experiment may be inconclusive.

This means that the results of the experiment are not clear and more research is needed.

Inconclusive results are often frustrating for scientists, but they provide an opportunity for further research.

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