Deck 29: Fueling the Bodys Metabolism

Question 1

The pancreas does NOT secrete ______.

A) chymotrypsin
B) bicarbonate
C) bile
D) lipase
E) amylase
F) glucagon

Answer 1

bile

Question 2

Scientists in Switzerland compared the total surface area of the small intestine in different species of bats. When the calculations were done as if the inner mucosal surface was smooth, the average inner surface area of the intestinal tube was 9.1 cm² in one species. The mucosal surface area increased to 48 cm² when the villi were factored in and reached a total of 0.13 m² after adding in the membrane surface area of the microvilli. Approximately what percent of the total surface area of the small intestine in these bats can be attributed to the membrane surface area of the microvilli?

A) 55%
B) 28%
C) 12%
D) 96%
E) 78%

Answer 2

96%

Question 3

When diet and exercise has failed to produce any significant weight loss, some patients who are seriously overweight elect to have stomach surgery. A procedure galled gastric sleeve surgery removes more than half of the stomach, leaving a tube (or sleeve) about the size of a banana. Following gastric sleeve surgery, patients would have the least trouble ____.

A) eating carbohydrate-rich foods
B) eating protein-rich foods
C) eating large chunks of food of relatively hard consistency
D) eating large amounts of food at one time

Answer 3

eating carbohydrate-rich foods

Question 4

The villi of the small intestine are invaginations of the _____________.

A) mucosa only
B) submucosa and mucosa
C) mucosa, submucosa and serosa
D) serosa only
E) muscularis only
F) serosa, muscularis, submucosa and mucosa

Question 5

The enzyme _______ has a pH optimum most similar to peak A in the above graph.

A) chymotrypsin
B) lipase
C) salivary amylase
D) pancreatic amylase
E) trypsin
F) pepsin

Question 6

An ambulance is rushing a man to the emergency room with a knife wound. The man was stabbed in the upper-right side of his abdomen and has a large amount of internal bleeding. What vital organ has most likely been damaged by the knife wound?

A) heart
B) liver
C) pancreas
D) stomach
E) appendix
F) gall bladder

Question 7

The above diagram shows four different types of transport proteins in the membranes of epithelial cells that line the small intestine. What protein most likely carries out coupled transport of both Na⁺ and glucose in the overall process of glucose absorption?

A) 1 (purple)
B) 2 (yellow)
C) 3 (blue)
D) 4 (green)
E) none of the above

Question 8

The liver regulates the concentration in the blood of all of the following EXCEPT _________.

A) steroid hormones
B) plasma proteins
C) alcohol and drugs
D) ammonia
E) chylomicrons

Question 9

Why doesn't the stomach acid just digest right through the wall of the stomach?

A) The pH of the stomach acid is not low enough to be able to digest the lining.
B) It does, we just rebuild the layers faster than they can be digested.
C) The lining of the stomach is protected by mucus.
D) Food prevents the acid from digesting the wall of the stomach.
E) Neutralizers are imbedded in the stomach lining.

Question 10

Enzymatic digestion of which class of nutrients would be most impaired by damage to the exocrine pancreas?

A) lipids
B) starch
C) proteins
D) sucrose
E) vitamins

Question 11

Lysozyme is an enzyme that is able to break down the cell walls of bacteria. Langur monkeys and ruminants (such as cows) are the only known mammals in which lysozyme functions in the stomach instead of in tears and saliva. The cow/langur enzyme also has five amino acid changes that are not present in other mammals. What is most likely to be true about lysozyme from langurs and cows compared to lysozyme from other mammals?

A) The five amino acids that langurs and cows have in common in their lysozyme were present in the common ancestor of all mammals.
B) These five amino acid changes somehow make the cow/langur lysozyme resistant to pepsin digestion.
C) Salivary and tear lysozyme functions best at a higher H⁺ ion concentration than the cow/langur enzyme.
D) These five amino acid changes alter the specificity of the enzyme, such that the cow/langur lysozyme attacks viruses instead of bacteria.

Question 12

Fish and clams are similar in that both use _____________ for gas exchange.

A) gills
B) lungs
C) the moist surface of their skin
D) tracheal tubes
E) the mantle

Question 13

Refer to the above diagram, which depicts gas exchange between water and the blood in a fish gill. The numbers represent percent saturation of O₂. What can you conclude from this diagram?

A) The fluid in tube AB flows from B to A.
B) Oxygen transfer is more efficient if the fluid in both tubes AB and CD stops moving during gas exchange.
C) The fluid in tube CD flows from D to C.
D) Tube AB represents the flow of blood and tube CD represents the flow of water.
E) The net direction of oxygen diffusion is from tube CD to tube AB.

Question 14

What step in the respiratory process of mammals requires the most energy?

A) exhalation
B) movement of carbon dioxide into red blood cells
C) binding of oxygen to hemoglobin
D) transport of oxygen across the walls of the alveoli
E) inhalation
F) activity of carbonic anhydrase in the lungs

Question 15

In the above graph, if Bracket A represents the tidal volume and Bracket B represents the vital capacity, respectively, of a young man, what does Bracket C represent?

A) anatomical dead space
B) air that is not used for gas exchange
C) air that helps keep the alveoli inflated (open) after forced exhalation
D) air from a previous breath that does not mix with newly-inhaled air of the next breath
E) air with a concentration of oxygen higher than that of air outside the body

Question 16

Tim, who is an avid cyclist, is struck by a car during an organized bike ride. Two of his ribs are broken, puncturing his chest wall on the right side. What will most likely happen to his lungs?

A) His right lung will collapse and his left lung will overinflate.
B) His left lung will be okay, but his right lung will collapse.
C) His left lung will be okay, but his right lung will overinflate.
D) Both lungs will overinflate.
E) His right lung will overinflate and his left lung will collapse.
F) Both lungs will collapse.

Question 17

The external gills of an adult axolotl are not as efficient as fish gills because___________.

A) axolotls are slow swimmers and all fish swim fast to ventilate their gills
B) blood flows though the axolotl gills more slowly than through fish gills
C) axolotl gills are not highly branched
D) water flows over the axolotl gills at many different angles
E) axolotl gills are covered by thick layers of cells

Question 18

The principal reason(s) for why gills were replaced with different types of respiratory organs in terrestrial animals is (are)
I-tissues and organs are less buoyant in air than in water.
II-countercurrent exchange is not very efficient at maximizing blood oxygenation levels.
III-water diffuses into air through evaporation.

A) I and III
B) just II
C) just I
D) II and III
E) I, II, and III

Question 19

Four-year old Sammy is having a temper-tantrum. In a final attempt to get his way, he yells to his mom, "I'm gonna hold my breath 'til I die!" What is the primary reason that Sammy's mom is unconcerned by this statement?

A) As Sammy holds his breath, the increasing levels of carbon dioxide in his blood will lead to stimulation of the respiratory control center in his brain.
B) As Sammy holds his breath, the decreasing levels of oxygen in his blood will lead to stimulation of the respiratory control center in his brain.
C) Sammy is too young to hold his breath for more than 30 seconds.
D) It is impossible for Sammy to control the contraction of his diaphragm and intercostal muscles since they are made up of smooth muscle.

Question 20

What is the likely outcome if you were able to force water through fish gills in the opposite direction to how it normally flows over the gills?

A) There would be no effect, and maximal oxygenation of blood would still occur.
B) The movement of carbon dioxide from the blood into the water would increase.
C) The direction of blood flow would reverse through the gills to compensate for the reversed direction of water flow.
D) Gas exchange would be inhibited and movement of oxygen into the blood would cease.
E) The blood's oxygen concentration would not be able to exceed 50%.

Question 21

A major genetic cause of lung damage due to destruction of the alveolar walls is deficiency of the protein alpha-1 anti-trypsin (AAT). AAT is an enzyme that inhibits the activity of another protein. What protein is most likely the normally-inhibited target of AAT?

A) collagen
B) carbonic anhydrase
C) elastin-specific protease
D) alpha and beta globulins
E) hemoglobin
F) albumin

Question 22

Tom is choking on a piece of steak that is stuck in his trachea, and he signals for his young son to call 911. It takes the paramedics three and a half minutes to reach his house. Will this be in time to save Tom (and why), or will Tom already be dead (and why)?

A) Tom will be alive since carbon dioxide and water will recombine in his red blood cells to form glucose and oxygen.
B) Tom will be alive since he had a reserve of about three-quarters of his hemoglobin still bound to oxygen when he started choking.
C) Tom will be dead since all the hemoglobin in his arterial blood will unload its oxygen during the first pass through the tissues after his last breath.
D) Tom will be dead due to the lowered pH of his blood.
E) Tom will be alive since the mitochondria in his muscles will release oxygen into the blood after he stops breathing.

Question 23

If each human lung contains about 300 million alveoli with a summed total surface area for gas exchange of 40 square meters, what is the approximate surface area of a single alveolus?

A) 133 square millimeters
B) 7.5 square micrometers
C) 750 square micrometers
D) 1.33 square micrometers
E) 7.5 square millimeters
F) 0.133 square millimeters

Question 24

What is the order of structures or spaces that a surgeon will pass through to operate on a human lung?

A) skin -> intercostal muscles -> pleural cavity -> parietal pleural membrane -> visceral pleural membrane -> lung tissue
B) skin -> pleural cavity -> intercostal muscles -> visceral pleural membrane -> parietal pleural membrane -> lung tissue
C) skin -> intercostal muscles -> parietal pleural membrane -> pleural cavity -> visceral pleural membrane -> lung tissue
D) skin -> visceral pleural membrane -> intercostal muscles -> pleural cavity -> parietal pleural membrane -> lung tissue
E) skin -> intercostal muscles -> visceral pleural membrane -> pleural cavity -> parietal pleural membrane -> lung tissue

Question 25

Every winter, many individuals tragically die in their sleep due to faulty heaters that leak carbon monoxide (CO) during the night. How does CO poisoning lead to death?

A) CO inhibits the chemosensitive neurons in the aortic and carotid bodies.
B) CO coats the surfaces of the alveoli, preventing diffusion of oxygen into the blood.
C) CO binds more tightly to carbonic anhydrase than does carbon dioxide.
D) CO binds more tightly to hemoglobin than does oxygen.
E) CO binds to oxygen, and the CO-oxygen complex cannot bind to hemoglobin.

Question 26

In 2012, Lance Armstrong was stripped of his record-setting, seven Tour de France titles and banned for life from competitive cycling because of his alleged use of performance-enhancing drugs (PEDs). One of the PEDs Armstrong was accused of taking is erythropoietin (EPO). Why would systematic use of this PED give Armstrong an unfair advantage in a bike race?

A) EPO stimulates formation of new capillary beds in skeletal and heart muscle.
B) EPO stimulates the formation of new alveoli in the lungs.
C) EPO stimulates red blood cell production by the bone marrow.
D) EPO increases cardiac output by stimulating the ventricles to contract more strongly.
E) EPO stimulates growth of skeletal muscle tissue.
F) EPO stimulates the production of more mitochondria in cardiac muscle cells.

Question 27

The graph below can be used to understand the forces underlying the movement of fluid between the blood and the interstitial fluid. What is a true statement concerning these processes?

A) Edema results from reduction of fluid flow in region A.
B) Normally, the net amount of fluid flow in region A is less than the net amount of fluid flow in region B.
C) Sodium ions contribute significantly to the movement of fluid in region B.
D) In people suffering from severe liver disease or protein starvation, the fluid flow in region B is increased.
E) Fluid leaves the blood in region A and returns to the blood in region B.

Question 28

The benefit provided by all hearts with two atria is

A) that blood is pumped into body tissues at high pressure.
B) complete separation of oxygenated and deoxygenated blood.
C) there is an extra place to store blood when the animal is at rest.
D) that there are two muscular regions for pumping blood out of the heart to different organs.
E) not all the blood has to pass through both sides of the heart.

Question 29

Jim is suffering from congestive heart failure, in which blood flow is backed up in his lungs and excess fluid is escaping the blood and accumulating in his lung tissue. If untreated, increasing pulmonary edema will lead to death by suffocation. What is the most-likely cause of Jim's congestive heart failure?

A) Jim's right atrioventricular valve (tricuspid valve) is not closing properly.
B) Contraction of his left ventricle is not keeping up with contraction of his right ventricle.
C) Jim's pulmonary semilunar valve is not opening properly.
D) Jim's SA node is malfunctioning.
E) Contraction of his right atrium is not keeping up with contraction of his left atrium.

Question 30

Under what circumstance would your body experience an increase in erythropoietin secretion?

A) after drinking 5 liters of water in just 2 hours
B) if you are suffering from dehydration
C) if you are suffering from hypertension
D) if you just moved from New York City to start training for a marathon in the 'Mile-High' city of Denver, Colorado
E) if your hematocrit is elevated above normal levels

Question 31

Blood returning to the left atrium of a frog heart has just come from ________________.

A) the lungs or the brain
B) the brain or the skin
C) the lungs only
D) the lungs or the skin
E) the skin only
F) the brain only

Question 32

The left ventricle in mammals is more muscular than the right ventricle because

A) the left ventricle is always contracting to maintain a systemic blood pressure.
B) the left ventricle has to pump blood throughout the body at high pressure.
C) the right ventricle only pumps blood into the right atrium.
D) the left ventricle pumps blood with a higher hematocrit than the blood that leaves the right ventricle.
E) the left ventricle pumps more total blood than the right ventricle.

Question 33

What would happen if your SA node and AV node fired at same time?

A) Your blood pressure would increase.
B) The QRS wave on an ECG would disappear, as it would be masked by the P wave.
C) The volume of blood leaving the ventricles would decrease.
D) Blood would be forced back into the atria from the ventricles.
E) The T wave on an ECG would disappear, as it would be masked by the QRS wave.

Question 34

Refer to the diagram below. What is the correct order of structures in the electrical excitation pathway that generates a normal heartbeat?

A) 2, 5, 1, 4, 6, 3
B) 3, 6, 2, 4, 1, 5
C) 1, 5, 4, 2, 3, 6
D) 1, 2, 3, 4, 5, 6
E) 3, 2, 6, 4, 5, 1
F) 6, 3, 2, 4, 5, 1

Question 35

In the blood clotting cascade mechanism, what is the first event that occurs following injury to a blood vessel?

A) conversion of fibrinogen to fibrin
B) fragmentation of a megakaryocyte to form platelets
C) aggregation of fibrin threads
D) secretion of fibrinogen into the blood
E) secretion of prothrombin into the blood

Question 36

The cardiac output is the volume of blood that is pumped out of the ventricles of the heart in the time interval of one minute. What factor most limits a person's maximal increase in cardiac output during exercise?

A) the rate at which oxygen is delivered to the cardiac muscle cells
B) the time available to fill the heart chambers with blood as the heart rate increases
C) the time it takes for electrical impulses to reach all parts of the heart
D) the total amount of blood in an individual
E) the rate at which cardiac muscle contracts

Question 37

During your annual physical, a nurse takes your blood pressure by wrapping a sphygmomanometer cuff around your upper arm, which modulates the flow of blood through your brachial artery. The nurse then enters a reading of 115/70 in your medical chart. These numbers mean that the

A) diastolic pressure is 115 and the systolic pressure is 70.
B) pressure in your brachial artery during ventricular contraction is 115, while the pressure during ventricular relaxation is 70.
C) pressure in your brachial artery during ventricular contraction is 115 while the pressure during atrial contraction is 70.
D) nurse heard sounds through the stethoscope only when the pressure in your brachial artery was exactly 115 and again when it was exactly 70.
E) pressure in the ventricles of the heart is 115 when the ventricles are contracting and 70 when the ventricles are relaxing.

Question 38

The brachial artery is the major artery in your upper arm. The figure below shows the blood pressure in the brachial artery of an average young adult, as it oscillates between the systolic pressure (120 mm Hg) and the diastolic pressure (75 mm Hg).
Superimposed on the right side of the graph is a tracing of the pressure in the left ventricle, which drops to close to zero mm Hg during diastole. What prevents the blood pressure in the brachial artery from similarly dropping to almost zero during diastole?

A) Forceful closing of valves in the subclavian and brachial arteries propels the blood forward during diastole.
B) Recoil of elastic fibers in the aorta propels the blood forward during diastole.
C) Forceful closing of the aortic semilunar valve propels the blood forward during diastole.
D) Rhythmic contraction of smooth muscle tissue in the subclavian and brachial arteries propels the blood forward during diastole.
E) Inhaling and exhaling propels the blood forward during diastole.

Question 39

You are taking a lab practical exam, and one station has pins in various internal structures of a bisected heart. You can orient yourself without picking up and examining the exterior of the heart because

A) the width of the external wall of the left ventricle is thicker than all the other chamber walls.
B) the ascending aorta exits from the right ventricle.
C) the width of the external wall of the right atrium is thicker than all the other chamber walls.
D) the width of the external wall of the left atrium is thicker than all the other chamber walls.
E) the width of the external wall of the right ventricle is thicker than all the other chamber walls.

Question 40

If an arteriole has a radius of 48 micrometers ( $\mu$ m) and a capillary in the same organ has a radius of 8 $\mu$ m, what is the difference in resistance in blood flow between the two?

A) The resistance in the arteriole is 6 times the resistance in the capillary.
B) The resistance in the capillary is 6 times the resistance in the arteriole.
C) The resistance in the arteriole is 48 times the resistance in the capillary.
D) The resistance in the capillary is 48 times the resistance in the arteriole.
E) The resistance in the arteriole is 96 times the resistance in the capillary.
F) The resistance in the capillary is 96 times the resistance in the arteriole.

Question 41

The figure below shows data for three different characteristics of blood vessels (orange, blue and green curves, respectively). What is correct to conclude from this graph?

A) The exchange of nutrients and respiratory gases between the blood and the interstitial fluid occurs where the blue curve plateaus out on the right.
B) Blood is propelled at the maximum of the orange curve by forceful closing of the aortic valve.
C) The orange curve represents the velocity of the blood flowing through each class of blood vessel.
D) The blue curve represents the average blood pressure in each class of blood vessel.
E) The green curve represents the total cross-sectional area of each class of blood vessel.

Question 42

Susie just squished a cockroach and its pale yellow hemolymph squirted out on the floor. If Susie analyzed the hemolymph, she would expect to find all of the following EXCEPT

A) cells that protect against foreign microbes.
B) ions.
C) water.
D) amino acids.
E) sugars.
F) hemoglobin.

Question 43

A mountain climber was rescued after spending 36 hours exposed to the elements on a slope of Mount Everest. Miraculously, the only permanent damage was to his toes, all of which had to be removed. What was the most likely cause of the damage to his toes?

A) metabolic (nitrogenous) wastes pooling in his feet
B) increased levels of carbon dioxide in his feet
C) the inability of his white blood cells to destroy infectious bacteria
D) blood pooling in the veins in his feet
E) vasoconstriction of the arteries to his legs and feet