AP1 module 3 quiz review questions

Question 1

1. Name the two main divisions of the digestive system organs.

Answer 1

1. The human digestive organs can be divided into those of the alimentary canal and the accessory digestive organs.

Question 2

2. Name the seven parts of the gastrointestinal tract.

Answer 2

2. The gastrointestinal tract is composed of the mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus.

Question 3

3. Name the six digestive system accessory organs.

Answer 3

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

Question 4

4. Review all the figures and diagrams, including the GI tract and accessory organs.

Answer 4

4. See module –review all figures and diagrams

Question 5

5. What structures respectively form these parts of the mouth?
   a. Opening
   b. Floor
   c. Walls
   d. Roof

Answer 5

5. What structures respectively form these parts of the mouth?

a. Opening = Lips
b. Floor = Tongue
c. Walls = Cheeks
d. Roof = Hard/soft palates

Question 6

6. List the two bones and the membrane to which the tongue is attached.

Answer 6

6. The tongue is attached to the hyoid bone and the mandible and the membranous lingual frenulum.

Question 7

7. How many teeth are there in an adult human and what do they do?

Answer 7

7. There are thirty-two teeth in the human mouth. Together they work to tear, crush and grind food to mechanically digest food

Question 8

8. What are the four types of teeth, how many of each type are there and what does each type do?

Answer 8

8. The teeth are composed of two chisel-shaped incisors for biting; one pointed canine for tearing; two fairly flat pre-molars for grinding; and three flat molars for crushing.

Question 9

9. What is the specific function of the salivary gland in the process of digestion?

Answer 9

9. Food is mixed and moistened with saliva (from the salivary glands) containing enzymes that begin the process of chemical digestion by breaking down starches.

Question 10

10. Where are taste buds located?

Answer 10

10. Taste buds are found primarily on the tongue but also on the surface of the mouth and the wall of the pharynx.

Question 11

11. Describe the function of the tongue in the digestive process.

Answer 11

11. The tongue grips the food, constantly repositions it between the teeth and forms it into a compact mass which is pushed back to the pharynx to begin the process of swallowing.

Question 12

12. What is a bolus?

Answer 12

12. A bolus is the compact mass of food formed by the combination of chewing by the teeth and repositioning by the tongue.

Question 13

13. List the 3 parts of the pharynx.

Answer 13

13. The pharynx is made up of three parts: the nasopharynx, the oropharynx, and the laryngopharynx.

Question 14

14. Through what sections of the pharynx does air travel? Through what sections of the pharynx does food travel?

Answer 14

14. Air enters the nose, continues through the nasopharynx, oropharynx and the laryngopharynx. Air then enters the trachea on its way to the lungs. Food and liquid enter the mouth, continue through the oropharynx and the laryngopharynx but then continue into the esophagus.

Question 15

15. What prevents food from entering the lungs and why is this necessary?

Answer 15

15. Food is prevented from entering the larynx by the epiglottis, a flap of elastic cartilage which covers the larynx when swallowing food or liquid.

Question 16

16. Describe how the muscular layers in the pharynx assist with food passage.

Answer 16

16. The pharynx has two types of skeletal muscles; a circumferential outer layer and an inner longitudinal layer which contract alternatively squeezing food into the esophagus.

Question 17

17. List and describe the tissue layers of the esophagus.

Answer 17

17. The esophagus contains 4 layers of tissue: the innermost layer is the mucosa which secretes mucus into the interior the gastrointestinal tract, the second layer is the submucosa which contains blood and lymph vessels, lymph nodes, nerves, and mucous glands, the third layer is the muscularis externa which is made of two layers of muscle: the outer longitudinal fibers and inner circumferential fibers and the outermost layer is the serosa which is made up of cells that make serous fluid.

Question 18

18. Explain peristalsis.

Answer 18

18. Peristalsis is the squeezing of food through the GI tract by the alternating contraction of the sets of longitudinal and circumferential muscles.

Question 19

19. What are the three main divisions of a tooth?

Answer 19

19. Each tooth is made of three main parts: the crown, the neck and the root

Question 20

20. What are the three types of papillae on the tongue? Which ones contain taste buds?

Answer 20

20. There are three types of papillae which help to grip food on the tongue: circumvallate, fungiform and filiform. Circumvallate and fungiform papillae both contain taste buds.

Question 21

21. Review all diagrams and figures in the module, including the teeth, tongue, taste buds, parts of the pharynx and esophagus.

Answer 21

21. See module –review all figures and diagrams

Question 22

22. Describe the shape of the stomach and its location relative to the abdomen and diaphragm.

Answer 22

22. The stomach is a backward C shaped organ that is located along the left side of the abdomen below the diaphragm.

Question 23

23. Describe the passage of food into and out of the stomach

Answer 23

23. Food enters the stomach from the esophagus via the cardioesophageal sphincter and exits the stomach via the pyloric sphincter into the small intestine.

Question 24

24. Describe the lesser curvature and the greater curvature.

Answer 24

24. The stomach has two curvatures: the concave lesser curvature which extends inward on the shorter side of the stomach and the convex greater curvature which extends outward on the longer side of the stomach.

Question 25

25. Describe the lesser omentum and the greater omentum.

Answer 25

25. The lesser omentum is a serous membrane which attaches the lesser curvature of the stomach to the liver and the greater omentum is a serous membrane which attaches the greater curvature of the stomach to the posterior wall of the body.

Question 26

26. List and describe the two functions of the stomach.

Answer 26

26. The stomach has two purposes. It is a temporary storage area for food, storing up to two liters of partially digested food. The muscular walls of the stomach contract vigorously and mix food with juices that are secreted whenever food enters the stomach, allowing food to be broken down into smaller pieces that are easier to digest.

Question 27

27. The pH of stomach is 1.3 - 3.5. What is this due to and what is its source and function?

Answer 27

27. The 1.3-3.5 pH of stomach contents is due to hydrochloric acid secreted by the parietal cells. The high acidity level kills bacteria and converts the inactive pepsinogen into the active enzyme pepsin.

Question 28

28. What is the source of the stomach enzyme pepsin and what is its function?

Answer 28

28. Inactive pepsinogen is secreted by the chief cells and converted into the active enzyme pepsin by HCl. Pepsin then begins the breakdown of proteins.

Question 29

29. What is a stomach ulcer?

Answer 29

29. A stomach ulcer is an open sore in the wall of the stomach

Question 30

30. Explain in detail how the stomach contents enter the small intestine

Answer 30

30. The pyloric sphincter valve, located at the base of the stomach, relaxes causing a small quantity of chyme to pass through the opening into the first part of the small intestine. This initiates a reflex that causes the muscles of the sphincter to contract and close the opening temporarily. Then the sphincter relaxes again and allows more chyme to enter.

Question 31

31. List the 3 sections of the small intestine. Which section is the shortest?

Answer 31

31. The first and shortest section of the small intestine is the duodenum. Second section is the jejunum and third is the ileum.

Question 32

32. What are the names of the valves which are located at the beginning and end of the small intestine?

Answer 32

32. The small intestine runs from the pyloric sphincter at the end of the stomach to the ileocecal valve at the large intestine.

Question 33

33. List the names of the 3 specialized structures in the wall of the small intestine.

Answer 33

33. The 3 specialized structures in the small intestine are circular folds, villi and microvilli.

Question 34

34. Where is bile formed and stored?

Answer 34

34. Bile is formed in the liver which is stored in the gallbladder.

Question 35

35. Describe in detail the 2 major functions of pancreatic juice.

Answer 35

35. Pancreatic juice contains sodium bicarbonate, which neutralizes the chyme and makes the pH of the small intestine slightly basic. Pancreatic juice also contains digestive enzymes that further digest every major component of food.

Question 36

36. Describe how fats, sugars and amino acids are absorbed by the small intestine.

Answer 36

36. Each small intestinal villus contains blood vessels and a lacteal lymphatic vessel. Sugars and amino acids enter villi cells and then are absorbed into the bloodstream. Glycerol and fatty acids enter villi cells and are reassembled into fat molecules, which move into the lacteals.

Question 37

37. What are the 3 functions of the liver that are important in digestion?

Answer 37

37. The 3 functions of the liver important in digestion are (1) it produces bile, which is stored in the gallbladder before entering the small intestine, where it emulsifies fats, (2) it stores glucose as glycogen and breaks down glycogen to glucose between meals to maintain a constant glucose concentration (homeostasis) in the blood, and (3) it produces urea from amino groups that are removed from excess amino acids.

Question 38

38. List the 8 regions of the large intestine.

Answer 38

38. (1) Cecum, (2) appendix, (3) ascending colon, (4) transverse colon, (5) descending colon, (6) sigmoid colon, (7) rectum, (8) anal canal

Question 39

39. What are the two sphincters of the anal canal?

Answer 39

39. The anal canal has an involuntary smooth muscle internal sphincter and a voluntary skeletal muscle external sphincter.

Question 40

40. List 4 functions of the large intestine.

Answer 40

40. The large intestine propel wastes, reabsorbs water, reabsorbs electrolytes and absorbs Vitamin K and certain B vitamins produced by intestinal bacteria.

Question 41

41. What are the 2 major physiological problems caused by diarrhea?

Answer 41

41. When materials pass through the colon too quickly, excess water is not reabsorbed, and diarrhea will result, which can lead to serious dehydration and electrolyte loss.

Question 42

42. List the content of feces.

Answer 42

42. Feces are about 75% water and 25% solid matter containing intestinal bacteria, undigested plant material, fats, bile pigments, inorganic material, mucus, and dead intestinal cells

Question 43

43. Review all figures and diagrams, including all regions of the stomach, intestines, and accessory organs

Answer 43

43. See module- review all figures and diagrams

Question 44

44. Name the 4 main functions performed by the digestive system.

Answer 44

44. The digestive system has four main roles that it performs: ingestion, digestion (both mechanical and chemical), absorption, and defecation.

Question 45

45. What digestive system functions are carried out by the mouth?

Answer 45

45. Ingestion and Digestion.

Question 46

46. Explain which digestive system functions are carried out by the stomach.

Answer 46

46. In the stomach mechanical digestion continues as muscles churn and mix the food, breaking it into smaller pieces in the form of chime which is moved to the small intestine by peristalsis. Chemical digestion continues as pepsin digests proteins.

Question 47

47. Explain which digestive system functions are carried out by the small intestine.

Answer 47

47. In the small intestine chemical digestion continues as enzymes from the pancreatic juices break down starches and proteins, and begin digestion of fat. Mechanical digestion continues as bile breaks down fat into smaller pieces. Absorption begins as digested food molecules, water and fat are absorbed into the bloodstream.

Question 48

48. Explain the two main hormones that are responsible for hunger and satiety.

Answer 48

48. Leptin and Ghrelin. Leptin is produced by adipose tissue (fat cells). The role of leptin is to alert the brain to turn off the hunger center in the brain and activate the satiety center when consuming a meal. Ghrelin is produced by the stomach and has the opposite role. Ghrelin travels to the brain and stimulates the hunger center as it deactivates the satiety center. Ideally, leptin and ghrelin work together to balance hunger and satiety.

Question 49

49. List the 5 biochemical materials needed by the body that are found in food.

Answer 49

49. Carbohydrates, proteins, and lipids are the major biochemical substances found in food needed by the body in large amounts. Vitamins and minerals are also needed in a much smaller amount.

Question 50

50. What are the 2 classes of carbohydrates and in what foods can each be found?

Answer 50

50. Carbohydrates are classified as starches and sugars. Milk and fruits such as apples or peaches contain sugar, while grains such as wheat and vegetables such as potatoes contain starches.

Question 51

51. What are the 3 classes of lipids?

Answer 51

51. Lipids can be divided into three categories: saturated fat, unsaturated fat, and cholesterol.

Question 52

52. What are the 2 classes of proteins and in what foods can each be found?

Answer 52

52. Proteins can be categorized as complete or incomplete proteins. Examples of complete proteins are meat, poultry, eggs, milk or dairy products, and soybeans; whereas, examples of incomplete proteins are grains, legumes, seeds, and nuts.

Question 53

53. What is the definition of an essential amino acid, how many essential amino acids are there for adults and where can they be found?

Answer 53

53. There are nine amino acids called essential amino acids required in an adult human diet since the body is unable to make these amino acids. Complete proteins contain all nine essential amino acids.

Question 54

54. What are the 2 classes of vitamins? How is a vitamin different than a carbohydrate, lipid or protein? Why can ingestion of excessive amounts of one type of vitamin be dangerous?

Answer 54

54. The 2 classes of vitamins are water-soluble vitamins and fat-soluble vitamins. Vitamins are organic compounds that are not consumed in metabolic reaction but help enzymes carry out the metabolic reactions which convert nutrients to materials need by the body. Fat-soluble vitamins are stored in body fat and ingestion of excessive amounts can be problematic.

Question 55

55. List 2 ways in which minerals are different than carbohydrates, lipids and proteins. List the seven minerals needed in the human diet and four foods which are good sources of these.

Answer 55

55. Minerals are inorganic compounds (not organic like carbohydrates, lipids and proteins) and are not used as fuel in metabolic reactions. Humans need the following seven minerals in their diets: calcium, chloride, magnesium, phosphorus, potassium, sodium, and sulfur. Foods such as milk, some meats, legumes and vegetables are the best sources of minerals.

Question 56

56. Define anabolism.

Answer 56

56. Anabolism is the set of reactions in which smaller molecules are combined to make larger molecules.

Question 57

57. How is the energy released from the breakdown of glucose used by the body?

Answer 57

57. The energy is released during the breakdown of glucose is used by the body to add a phosphate to an adenosine diphosphate (ADP) molecule and make adenosine triphosphate (ATP).

Question 58

58. Describe cellular respiration.

Answer 58

58. During cellular respiration, glucose combines with oxygen to form carbon dioxide, water, and ATP

Question 59

59. Describe glycolysis.

Answer 59

59. In glycolysis glucose is broken down into two pyruvic acid molecules and two ATP molecules are formed.

Question 60

60. Describe the citric acid cycle (TCA cycle).

Answer 60

60. In the citric acid (TCA) cycle the pyruvic acid product of glycolysis is converted to carbon dioxide forming some additional ATP.

Question 61

61. Describe the electron transport chain.

Answer 61

61. In the electron transport chain hydrogen atoms formed during glycolysis and the TCA cycle are converted to water releasing energy which is used to add phosphate to ADP to form ATP.

Question 62

62. How is the energy released in the breakdown of glucose converted to a form usable by the cells?

Answer 62

62. The energy released in the breakdown of glucose allows the body to add a phosphate to an adenosine diphosphate (ADP) molecule and make adenosine triphosphate (ATP) which is then used by cells as a source of energy to perform cellular activities.

Question 63

63. How does the energy formed in fat catabolism compare to that formed in carbohydrate metabolism?

Answer 63

63. Lipid metabolism yields twice the energy formed during glucose metabolism.

Question 64

64. Name, tell the location of and explain in detail the first stage of lipid breakdown.

Answer 64

64. Lipid metabolism occurs in the liver by a process known as beta-oxidation to form acetic acid which is further catabolized by the TCA cycle to carbon dioxide forming some

Question 65

65. Why are proteins not usually used as a body energy source and when are they used?

Answer 65

65. Proteins are the building blocks for the cells and are therefore preserved by the body only being used to make ATP when carbohydrates and fats are unavailable to the body.

Question 66

66. What is the first step in the oxidation of an amino acid formed from a protein?

Answer 66

66. When proteins must be used to form ATP, the amino group is removed from the protein to form ammonia.

Question 67

67. Explain in detail how ammonia is removed from the body.

Answer 67

67. Ammonia is combined with carbon dioxide to make urea which is excreted in the urine.

Question 68

68. Review all diagrams and figures.

Answer 68

68. See module- review all diagrams and figures.