Download Mock Exam III Answers 1. False. Our diet has to be a combination of

Mock Exam III Answers
1. False. Our diet has to be a combination of: organic raw materials, energy for internal and external
work, and essential nutrients. We have to take all of this in, because we can’t make it on our own.
2. False. 20 amino acids are used for protein synthesis, but only 8 of those are essential and can’t be made
from precursors. What type of food can you take in order to obtain all of these? What doesn’t provide all
8 of these? (Beans and legumes only have 7, animal proteins have all 8).
3. True. Most fatty acids aren’t essential; however, linoleic acid is an essential FA.
4. False. Coenzymes, vitamin D, and vitamin A are all vitamins. Some are water-soluble and some are
fat-soluble.
5. False. Folate is vitamin B9 that is required for proper neural tube development, and si now added to
flour. Vitamin A is required in pigment.
6. True. Minerals are inorganic nutrients required in small amounts. Calcium is needed for the structure
of the skeleton, muscle contraction, and signaling in the nervous system.
7. False. Food in the pharynx triggers the swallowing reflex. The larynx is the voice box. The pharynx is
the area before the trachea and esophagus. The esophageal sphincter then relaxes, the larynx rises, and the
epiglottis.
8. False. The top of the esophagus is made up of voluntary muscles and is striated. The rest is made up of
involuntary muscles that carry out peristalsis with smooth muscles that push food to the stomach all the
way to the cardiac sphincter.
9. False. Most absorption occurs in the small intestine, as well as most digestion.
10. False. Parietal cells in the stomach DO release HCl; however, it helps the stomach reach its optimal
pH of 2, not 5. The stomach has to be very acidic to carry out its functions.
11. False. Chief cells secrete pepsinogen, not pepsin. The pepsinogen is made into an active protease,
pepsin, by HCl. The pepsin is the first area of the body where protein digestion occurs.
12. E. **Correction: e should be: b and c. The small intestine has folds called villi, and each villi has fin
extensions called microvilli. The microvilli is what makes up the brush border. The brush border is
associated with digestive enzymes: proteases and carbohydrases. Lipases are only found released from the
pancreatic duct.
13. C. First protease food encounters. Means that it catalyzes the hydrolysis of internal peptide bonds. A
and B are exopeptidases.
14. D. Via the pancreatic duct. Trypsin and chymotrypsin are types of endopeptidases. They have inactive
precursors that have to be activated. Carboxypeptidase is a exopeptidase.
15. D. Dipeptidases cleave dipeptides into two amino acids. Important after all of the others break the
proteins down.
16. False. Salivary amylase, as well as pancreatic amylase, is a polysaccharidase which means that it
breaks large polysaccharides into disaccharides. Then disaccharidase associated with the brush border has
to break the disaccharides into monosaccharides.
17. True. Described in number 16.
18. True. It is an accessory organ, because it produces bile which is stored and released from the
gallbladder after production.
19. C. Pepsin is the active protease found in the stomach where the pH is the lowest in all of the digestive
tract. It is a endopeptidase.
20. A. Mucus is found in the stomach and is released by mucus cells and protects the stomach. Mucin is
found in the mouth and used to protect there. What is chyme?
21. False. Refer to number 16. Starch and glycogen are the polysaccharides.
22. D. Involuntary smooth muscle action.
23. B.
24. D. Sodium bicarbonate is released by the pancreas and neutralizes the pH of the digestive juices that
are in the small intestine.
25. C. It does not directly carry the products of digestion throughout the body, but it does provide
enzymes that are needed.
26. E. The liver produces the bile and sends it to the gallbladder to be stored. Bile keeps fat drops for
coalescing, decreases the size of fat globules and increases the surface area for the lipase from the
pancreas to work on them.
27. D.
28. C. A is incorrect, because fats are neutralized before they are digested. B is incorrect because those
enzymes are not found in chyme. D. is incorrect, because even though chyme eventually moves to the
large intestine, it is not ACID chyme. E. is incorrect, because this happens in the small intestine right after
everything is neutralized. Acid chyme is the digested food leaving the stomach at the pyloric sphincter.
29. E. Gallbladder and liver could be matched with bile.
30. True. Water is added in to bonds to break them apart.
31. A. This allows food to move into the esophagus. The larynx rises, test this out when you swallow, and
the epiglottis covers the glottis so food does not enter the voice box/trachea area.
32. D. Fatty acids are absorbed into cells by simple diffusion, because they are fat-soluble. Glycerol,
however, is absorbed using facilitated diffusion, as well. Then the chylomicron is exocytosed out of the
cell to be absorbed into the blood stream. The facilitated diffusion is used by pairing these molecules in a
and c with sodium and moving it with sodium’s diffusion gradient.
33. C. Monoglycerides are also absorbed into the cell along with fatty acids and is packaged into a
micelle beforehand that can just pass into the cell by simple diffusion.
34. A. This is the part of the heart that pumps blood out into the body. This oxygenated blood is then
carried to the systemic tissues, becomes deoxygenated, and is then carried back to the heart at the right
atrium. The blood then enters the right ventricle and goes to the lungs from there via the pulmonary artery
using the pulmonary semilunar valve, (ONLY ARTERY THAT CARRIES DEOXYGENATED
BLOOD!). Blood becomes oxygenated then enters the heart via the pulmonary vein, (ONLY VEIN
THAT CARRIES OXYGENATED BLOOD!), into the left atrium. Then the blood enters the left
ventricle and is pumped back out.
35. E. AV node is found between the atria and ventricles and helps the signal spread to the septum at the
Bundle of His, and then spreads to the Purkinje fibers which send signals the ventricles from the bottom
up.
36. A. That is the reason why we have capillary sphincters. Remember: as cross-sectional area increases,
the pressure drops.
37. A. This is initiated before the AV node in 35.
38. B. The fluid is returned to the blood right before the blood loops back around to the right atrium. It
has to be collected by the lymph vessels so it will not pool up in the interstitial space.
39. False. Systolic is the blood pressure measured at a heart contraction and is on average 120-130 mm
hg, where diastolic is usually around 70 and is measured at relaxation.
40. C. What does autorhythmic mean?
41. B. This is the purpose of these cell fragments.
42.False. Diastole, relaxation. That is when the blood from the atria is pooling into the ventricles. The
semilunar valves are closed. Near end atria contract topping off the two ventricles. What happens during a
systole?
43. E. This is false, but does refer to the internal volume of cardiac muscle fibers. Does E apply to
skeletal muscle fibers?
44. True. Intercalated discs are found between muscle fibers and include these and gap junctions.
45. A.
46. B. Gastric glands do have a lot of SA; however, they do not absorb like the small intestine does.
47. B. Know pathway of each!
48. E. All is true.
49. B. Where are these located?
50. C. Skipped part where blood exits right ventricle to enter the lungs.
51. False. This is desmosomes. Gap junctions connect the cytosol, so that cells can be electrically coupled
and action potentials can flow between cells very fast.
52. True.
53. False. By oxidizing glucose. What is the formula?
54. E. A is wrong, because even though there are arteries in veins involved, this mechanism would not
work if the capillaries weren’t situated between the arteries and veins and allowed the blood to
collectively move from the deoxygenated side to the oxygenated side. B is wrong; it has to be in the
opposite direction. It is very efficient, picks up 80-90% of the oxygen in the water. Occurs when
oxygenated water passes by the de-oxygenated blood.
55. D. Are only once cell layer thick, total to 300 MILLION, stem from the bronchioles, and are heavily
vascularized.
56. False. As pressure increases, volume decreases. P1V1=P2V2
57.C. It is not only the intercostals, it is also the diaphragm.
58. A. Visceral pleura is the epithelial layer that covers the lungs. B is incorrect, because it is called
intrapleural fluid. Pleura covers the lungs and the thoracic wall, but c is incorrect because parietal pleura
cover the thoracic wall. Intrapleural fluid allows the lungs to adhere to the thoracic wall.
59. D. Jellyfish do not use gills nor any other developed respiratory structures. Lungs are more efficient;
gills use up 33% of a fish’s energy. They do prevent evaporative loss. They are able to abstract up to 8590% of the oxygen from the water.
60. E. The gill filaments attach to the gill arch. Within each gill filament are multiple lamellae that water
flows between during the countercurrent exchange mechanism.