ATI TEAS 7 — All Questions

A chart lists a patient's temperatures as 98.6, 100.2, 101.4, and 99.8 degrees Fahrenheit. What is the range of these readings?

• a.101.4 degrees
• b.2.8 degrees✓
• c.100.0 degrees
• d.1.6 degrees

Range is the highest value minus the lowest: 101.4 - 98.6 = 2.8 degrees. The value 1.6 uses the wrong pair, 100.0 is close to the mean, and 101.4 is simply the maximum.

Weekly clinic visits fell from 250 to 200. What was the percent decrease?

• a.25%
• b.80%
• c.50%
• d.20%✓

The drop is 50, and 50 / 250 = 0.20, which is 20 percent. Using 200 as the base gives 25 percent, 50 is the raw decrease rather than a rate, and 80 percent is what remains rather than what was lost.

On a scale drawing, 3 centimeters represents 20 kilometers. How many kilometers does 12 centimeters represent?

• a.80 kilometers✓
• b.1.8 kilometers
• c.240 kilometers
• d.60 kilometers

Set up 3/20 = 12/x, so 3x = 240 and x = 80 kilometers. The value 240 skips the division by 3, 60 triples 20 instead of scaling by four, and 1.8 divides in the wrong direction.

Evaluate the product: -3 x (-8)

• a.-24
• b.24✓
• c.11
• d.-11

A negative times a negative gives a positive, so the product is 24. Answering -24 keeps the sign negative, and 11 or -11 comes from adding the two numbers rather than multiplying.

What is the value of the square root of 81 plus the square root of 16?

• a.13✓
• b.5
• c.36
• d.the square root of 97

The square root of 81 is 9 and the square root of 16 is 4, so the sum is 13. Adding before taking a root gives the square root of 97, 5 subtracts instead of adding, and 36 multiplies 9 by 4.

A jar holds 20 marbles, 5 of which are red. If one marble is drawn at random, what is the probability that it is NOT red?

• a.3/4✓
• b.1/5
• c.1/4
• d.5/20

Fifteen of the 20 marbles are not red, so the probability is 15/20, which reduces to 3/4. The choices 1/4 and 5/20 give the probability of drawing a red marble, and 1/5 uses the wrong total.

A saline solution is labeled 8% sodium chloride. Written as a decimal, 8% is:

• a.8.0
• b.0.08✓
• c.0.8
• d.0.008

Percent means per hundred, so dividing by 100 moves the decimal point two places to the left: 8% = 0.08. Moving it one place gives 0.8, moving it three gives 0.008, and 8.0 does not convert the percentage at all.

Which valve separates the right atrium from the right ventricle?

• a.The mitral valve
• b.The aortic valve
• c.The pulmonary semilunar valve
• d.The tricuspid valve✓

The tricuspid valve sits between the right atrium and right ventricle. The mitral valve occupies the matching position on the left side, while the pulmonary semilunar and aortic valves guard the exits of the two ventricles rather than the entrances.

Which vessel carries deoxygenated blood away from the heart toward the lungs?

• a.The aorta
• b.The pulmonary vein
• c.The pulmonary artery✓
• d.The superior vena cava

The pulmonary artery is the one artery carrying oxygen-poor blood, moving it from the right ventricle to the lungs. Pulmonary veins return oxygen-rich blood to the heart, the aorta distributes oxygen-rich blood to the body, and the vena cava brings blood into the heart rather than away from it.

Which structure acts as the heart's natural pacemaker?

• a.The sinoatrial node✓
• b.The Purkinje fibers
• c.The bundle of His
• d.The atrioventricular node

The sinoatrial node in the right atrium fires fastest and therefore sets the rhythm. The atrioventricular node, bundle of His, and Purkinje fibers conduct that signal onward and can pace the heart only if the sinoatrial node fails.

Which type of blood vessel is the site where oxygen and nutrients pass into the tissues?

• a.Capillaries, whose walls are one cell thick✓
• b.Veins, because they contain one-way valves
• c.Arterioles, because they control blood flow
• d.Arteries, because they carry blood at the highest pressure

Capillary walls are a single layer of endothelium, thin enough for substances to diffuse across. Arteries and arterioles distribute blood under pressure and veins return it, but none of those has walls thin enough for exchange.

Which component of blood is primarily responsible for clotting?

• a.Red blood cells
• b.Plasma proteins called albumins
• c.Platelets✓
• d.White blood cells

Platelets, also called thrombocytes, aggregate at an injury and trigger the clotting cascade. Red cells carry oxygen, white cells defend against infection, and albumin maintains osmotic pressure rather than forming clots.

Why is the wall of the left ventricle thicker than the wall of the right ventricle?

• a.It receives blood directly from the lungs
• b.It contains more valves than the right side
• c.It must pump blood to the whole body✓
• d.It holds a much larger volume of blood

The left ventricle generates the higher pressure needed for systemic circulation, so its muscular wall is thicker. Both ventricles eject roughly the same volume, each has one outflow valve, and receiving blood from the lungs is the job of the left atrium.

A blood pressure reading is written as 120/80. What does the lower number represent?

• a.The number of heartbeats per minute
• b.Pressure while the ventricles contract
• c.The volume of blood pumped per beat
• d.Pressure while the ventricles relax✓

The lower figure is diastolic pressure, measured between contractions when the ventricles fill. The upper figure is systolic pressure during contraction, and neither number reports heart rate or stroke volume.

Which mineral is a required part of the hemoglobin molecule?

• a.Potassium
• b.Calcium
• c.Iron✓
• d.Sodium

Each hemoglobin molecule holds four iron-containing heme groups, and the iron is what binds oxygen. Calcium supports bone and clotting, while sodium and potassium are electrolytes involved in fluid balance and nerve signaling.

In which structures of the lungs does gas exchange with the blood actually occur?

• a.The alveoli✓
• b.The bronchi
• c.The pleural membranes
• d.The trachea

Alveoli are thin-walled air sacs wrapped in capillaries, which is where oxygen and carbon dioxide diffuse. The trachea and bronchi are conducting airways only, and the pleural membranes reduce friction as the lungs move.

Which structure closes over the opening of the larynx during swallowing?

• a.The epiglottis✓
• b.The vocal cords
• c.The soft palate
• d.The uvula

The epiglottis folds down over the laryngeal opening so food passes into the esophagus instead of the airway. The soft palate and uvula close off the nasal passages, and the vocal cords produce sound rather than sealing the airway during swallowing.

By what process do oxygen and carbon dioxide move across the alveolar membrane?

• a.Active transport requiring ATP
• b.Filtration driven by blood pressure
• c.Simple diffusion down concentration gradients✓
• d.Endocytosis by the alveolar cells

Each gas moves passively from where it is more concentrated to where it is less concentrated, which is diffusion and requires no energy. Active transport, filtration, and endocytosis all describe other mechanisms that do not govern alveolar gas movement.

Which sequence correctly traces inhaled air from the throat to the gas-exchange surface?

• a.Trachea, alveoli, bronchioles, bronchi
• b.Trachea, bronchi, bronchioles, alveoli✓
• c.Bronchioles, bronchi, trachea, alveoli
• d.Bronchi, trachea, alveoli, bronchioles

Air passes down the trachea, divides into the bronchi, narrows into bronchioles, and ends at the alveoli. The other sequences place a smaller branch before the larger one it comes from, which reverses the branching pattern of the airway.

What is the primary function of surfactant in the lungs?

• a.It carries oxygen from the alveoli into the bloodstream
• b.It triggers the cough reflex when irritated
• c.It traps dust particles entering the airway
• d.It reduces surface tension so alveoli stay open✓

Surfactant lowers the surface tension of the fluid lining the alveoli, preventing them from collapsing at the end of expiration. Hemoglobin carries oxygen, mucus and cilia trap particles, and sensory nerves trigger coughing.

Which enzyme in saliva begins the chemical digestion of starch in the mouth?

• a.Amylase✓
• b.Trypsin
• c.Lipase
• d.Pepsin

Salivary amylase starts breaking starch into smaller sugars while food is still being chewed. Pepsin acts on protein in the stomach, trypsin acts on protein in the small intestine, and lipase acts on fats.

In which organ does the chemical digestion of protein begin?

• a.The mouth
• b.The stomach✓
• c.The esophagus
• d.The large intestine

Hydrochloric acid in the stomach converts pepsinogen to pepsin, which starts splitting proteins. The mouth begins starch digestion instead, the esophagus only transports food, and the large intestine mainly absorbs water.

What is the primary role of bile in digestion?

• a.It emulsifies fats into smaller droplets✓
• b.It neutralizes stomach acid entering the intestine
• c.It chemically breaks peptide bonds in protein
• d.It absorbs vitamins through the intestinal wall

Bile is a detergent rather than an enzyme; it breaks large fat globules into small droplets so lipase can reach more surface. Pancreatic bicarbonate neutralizes acid, proteases break peptide bonds, and absorption is carried out by the intestinal lining.

Which organ stores and concentrates bile until it is needed?

• a.The gallbladder✓
• b.The pancreas
• c.The liver
• d.The first part of the small intestine

The gallbladder holds bile between meals and releases it when fatty food arrives. The liver produces bile rather than storing it, the pancreas makes digestive enzymes, and the first part of the small intestine is where bile is delivered.

What is peristalsis?

• a.The absorption of water in the large intestine
• b.Wavelike muscle contractions that move food along✓
• c.The chemical breakdown of nutrients by enzymes
• d.The release of hormones that signal hunger

Peristalsis is the rhythmic squeezing of smooth muscle that propels contents through the digestive tract. Enzyme action, water absorption, and hunger signaling are separate processes that do not describe this movement.

What is the main function of the large intestine?

• a.Absorbing water and forming solid waste✓
• b.Absorbing the majority of amino acids
• c.Producing most digestive enzymes
• d.Secreting acid to kill swallowed bacteria

The large intestine reclaims water and electrolytes, compacting the remaining material into feces. Most enzymes come from the pancreas, nutrient absorption happens in the small intestine, and acid secretion occurs in the stomach.

How do villi and microvilli improve the function of the small intestine?

• a.They neutralize acid arriving from the stomach
• b.They secrete bile into the intestinal lumen
• c.They slow food down so digestion lasts longer
• d.They greatly increase the surface area for absorption✓

These finger-like projections multiply the absorptive surface many times over, so more nutrients cross into the blood and lymph. Bile comes from the liver, and neither slowing transit nor neutralizing acid is what the projections themselves accomplish.

Which organ produces digestive enzymes and also releases insulin and glucagon?

• a.The pancreas✓
• b.The spleen
• c.The thymus gland
• d.The liver

The pancreas has both roles: an exocrine portion releasing enzymes into the duodenum and islet cells releasing insulin and glucagon into the blood. The spleen filters blood, the liver processes nutrients and makes bile, and the thymus matures T cells.

What is the functional unit of the kidney?

• a.The nephron✓
• b.The renal pelvis
• c.The ureter
• d.The alveolus

Each kidney contains about a million nephrons, and every one filters blood and forms urine. The ureter drains urine away, the renal pelvis collects it, and the alveolus belongs to the lungs.

In which part of the nephron does filtration of blood first occur?

• a.The distal tubule
• b.The collecting duct
• c.The glomerulus✓
• d.The loop of Henle

Blood pressure forces water and small solutes out of the glomerular capillaries into the surrounding capsule, which is the first step. The loop of Henle, distal tubule, and collecting duct then modify that filtrate by reabsorption and secretion.

Which tube carries urine from the kidney to the urinary bladder?

• a.The ureter✓
• b.The urethra
• c.The renal artery
• d.The vas deferens

The ureter runs from each kidney down to the bladder. The urethra carries urine from the bladder out of the body, the renal artery delivers blood into the kidney, and the vas deferens is part of the male reproductive tract.

Antidiuretic hormone acts on the kidney to produce what effect?

• a.More dilute urine in larger amounts
• b.More glucose returned to the blood
• c.More sodium excreted in the urine
• d.More water reabsorbed and less urine✓

Antidiuretic hormone makes the collecting ducts permeable to water, so water returns to the blood and urine volume falls. Aldosterone is the hormone that governs sodium handling, and glucose reabsorption is not under this hormone's control.

Besides removing waste, which of these is a function of the kidneys?

• a.Producing bile for the digestion of fats
• b.Producing antibodies against infection
• c.Secreting insulin to lower blood glucose
• d.Regulating the pH of the blood✓

The kidneys adjust bicarbonate and hydrogen ion excretion, which is a major control on blood pH. Bile comes from the liver, insulin from the pancreas, and antibodies from plasma cells of the immune system.

Which waste product in urine comes mainly from the breakdown of proteins?

• a.Bilirubin
• b.Carbon dioxide
• c.Lactic acid
• d.Urea✓

Amino acids are deaminated in the liver, and the resulting ammonia is converted to urea for excretion by the kidneys. Bilirubin comes from broken-down hemoglobin, lactic acid from anaerobic metabolism in muscle, and carbon dioxide is exhaled rather than excreted as a urinary waste.

Which term describes the body's tendency to maintain a stable internal environment?

• a.Mitotic cell division
• b.Metabolism
• c.Homeostasis✓
• d.Diffusion

Homeostasis is the regulated stability of conditions such as temperature, pH, and glucose. Metabolism is the sum of chemical reactions, diffusion is one transport mechanism, and mitotic cell division produces new body cells.

What is the primary function of the myelin sheath on a neuron?

• a.It anchors the neuron to surrounding connective tissue
• b.It receives incoming signals from neighboring neurons
• c.It speeds the conduction of the nerve impulse✓
• d.It manufactures the neurotransmitters released at the synapse

Myelin insulates the axon so the impulse jumps between gaps and travels far faster than it would on a bare axon. Neurotransmitters are made in the cell body and terminals, dendrites receive signals, and glial cells rather than myelin provide structural support.

Which division of the nervous system prepares the body for 'fight or flight'?

• a.The somatic division
• b.The sympathetic division✓
• c.The parasympathetic division
• d.The enteric division

Sympathetic activity raises heart rate, dilates airways, and shunts blood to skeletal muscle. The parasympathetic division does the opposite by promoting rest and digestion, the somatic division controls voluntary movement, and the enteric division regulates the gut.

Which part of the brain coordinates balance and smooth voluntary movement?

• a.The occipital lobe of the cerebrum
• b.The medulla oblongata
• c.The hypothalamus
• d.The cerebellum✓

The cerebellum fine-tunes posture, balance, and the timing of movement. The medulla governs automatic functions such as heart rate and breathing, the hypothalamus regulates temperature and hunger, and the occipital lobe processes vision.

Damage to the medulla oblongata is life-threatening mainly because it controls:

• a.The sense of balance while walking
• b.The interpretation of visual information
• c.The formation of new long-term memories
• d.Heart rate and the rhythm of breathing✓

The medulla contains the cardiac and respiratory centers, so injury there can stop the heartbeat or breathing. Memory is a function of the hippocampus and cortex, vision belongs to the occipital lobe, and balance is handled by the cerebellum and inner ear.

What is a synapse?

• a.The branching region that receives incoming signals
• b.The junction where a signal passes between neurons✓
• c.The insulating layer wrapped around a long axon
• d.The portion of the neuron that contains the nucleus

A synapse is the gap where one neuron communicates with the next, usually by releasing a neurotransmitter. The insulating layer is myelin, the receiving branches are dendrites, and the region holding the nucleus is the cell body.

In a simple reflex such as the knee-jerk, where is the response coordinated?

• a.In the spinal cord✓
• b.In the cerebellum
• c.In the pituitary gland
• d.In the frontal lobe of the cerebrum

A reflex arc travels from sensory neuron to spinal cord to motor neuron, which is why the response happens before the brain interprets it. The cerebrum and cerebellum may register the event afterward, and the pituitary is an endocrine gland with no role in reflexes.

Which structure connects a skeletal muscle to a bone?

• a.A synovial membrane
• b.A ligament
• c.Cartilage
• d.A tendon✓

Tendons are dense connective tissue joining muscle to bone. Ligaments join one bone to another, cartilage cushions joint surfaces, and the synovial membrane secretes lubricating fluid inside a joint capsule.

Which two protein filaments slide past each other to shorten a muscle fiber?

• a.Actin and myosin✓
• b.Keratin and albumin
• c.Collagen and elastin
• d.Fibrin and thrombin

The sliding filament model describes myosin heads pulling on actin filaments to shorten the sarcomere. Collagen and elastin are structural proteins of connective tissue, keratin and albumin are unrelated to contraction, and fibrin and thrombin belong to blood clotting.

Skeletal muscle is best described as:

• a.Voluntary and without any striations
• b.Involuntary and striated in appearance
• c.Voluntary and striated in appearance✓
• d.Involuntary and without striations

Skeletal muscle is under conscious control and shows a banded pattern under the microscope. Cardiac muscle is striated but involuntary, and smooth muscle is both involuntary and unstriated, so the other combinations describe those tissues instead.

When the biceps contracts to bend the elbow, what does the triceps do?

• a.It detaches from the bone to allow movement
• b.It contracts with equal force at the same time
• c.It contracts first and then shortens further
• d.It relaxes and lengthens as the opposing muscle✓

Muscles work in antagonistic pairs: one shortens while its partner relaxes, because muscles can only pull. Simultaneous equal contraction would lock the joint, and muscles never detach from bone during normal movement.

Approximately how many bones are in the adult human skeleton?

• a.150
• b.300
• c.450
• d.206✓

An adult skeleton has about 206 bones. Infants are born with roughly 300, many of which fuse during growth, so 300 describes a newborn rather than an adult, and 150 and 450 are far from either figure.

Which tissue inside certain bones produces red and white blood cells?

• a.Red bone marrow✓
• b.Articular cartilage
• c.Compact bone tissue
• d.The periosteum

Red marrow is the site of hematopoiesis, forming red cells, white cells, and platelets. Compact bone provides strength, articular cartilage covers joint surfaces, and the periosteum is the membrane wrapping the outside of a bone.

The knee and the elbow are examples of which type of joint?

• a.Immovable fibrous joints
• b.Hinge joints✓
• c.Pivot joints
• d.Ball-and-socket joints

A hinge joint permits bending and straightening in one plane, which is how the knee and elbow move. Ball-and-socket joints such as the hip rotate in many directions, pivot joints allow rotation around an axis, and fibrous joints such as skull sutures barely move.

Besides support and movement, which mineral do bones store and release for the body?

• a.Zinc
• b.Calcium✓
• c.Iron
• d.Iodine

Bone is the body's calcium reservoir, releasing it when blood levels fall. Iodine is stored in the thyroid, most iron is held in hemoglobin and the liver, and zinc is not stockpiled in the skeleton.

Which cells break down bone tissue so that minerals can be released into the blood?

• a.Erythrocytes
• b.Osteoblasts
• c.Chondrocytes
• d.Osteoclasts✓

Osteoclasts resorb bone matrix, while osteoblasts do the opposite by depositing new bone. Chondrocytes maintain cartilage and erythrocytes are red blood cells, so neither remodels bone.