Download KEY: Unit 8 RG

Anatomy/Physiology Study Guide
Unit 8- Digestive System
Words to digest and define:
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Cellulose is called FIBER on food labels.
alimentary canal- digestive system “tube” from mouth to anus
bolus- chewed up ball of food in mouth (& through esophagus)
peristalsis- muscular movements moving material through digestive system (esophagus through large
intestine)
rugae- folds of the stomach
chyme- chewed up food in stomach
Some tasty tidbits to answer:
1. Complete the following table:
Macromolecule (polymer) Starts digestion in the
Ends digestion in the
proteins
carbohydrates
Nucleic acids
Lipids (fats)
Small intestine
Small intestine
Small intestine
Small intestine
Stomach
Mouth
Small intestine
Small intestine
End products of digestion
(monomers)
Amino acids
Monosaccharides
nucleotides
Glycerol & fatty acids
chains
2. Differentiate between chemical digestion and mechanical digestion.
-chemical: enzymes!
-mechanical: smashing (teeth; stomach)
3. The following enzymes digest (break the bonds of) what type of macromolecule?
 salivary amylase- carbohydrates
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pancreatic amylase- carbohydrates
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lipases- lipids
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nucleases- nucleic acids
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proteases- proteins
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pepsin- protease example (in stomach)
o
How is pepsinogen different than pepsin? pepsinogen is inactive (needs HCl)
4. List three of the five functions of saliva.
1) moisten food
2) taste possible
3) cleanses the mouth
4) begins chemical digestion of carb’s
5) bind food
5. List and briefly describe the functions of the four layers of the alimentary canal.
Mucosa (most inside layer)  in intestines, forms villi
Submucosa  loose connective tissue
Muscular  movement (peristalsis)
Serosa  protection
6. What enzyme begins the chemical digestion of carbohydrates? amylase
7. What is the function of the:
 cardiac sphincter- top of stomach (keep chyme out of esophagus)
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pyloric sphincter- bottom of stomach (regulate chyme movement into duodenum)
8. Where are all the following cells located? STOMACH What do they specifically secrete (indicate below)?
 chief cells: pepsinogen
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parietal cells: hydrochloric acid (HCl)
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goblet cells: mucus
9. Besides killing bacteria on your food, what is the role of the hydrochloric acid in your stomach?
Activates pepsinogen into pepsin
10. Where does the pancreatic duct connect into and what does it carry (what’s in pancreatic juice)?
Duodenum; digestive enzymes!! (for all 4 types of macromolecules) AND bicarbonate solution
11. When acidic chyme enters the duodenum, what series of secretion is activated? (Ex: acidic chyme causes
the SMALL INTESTINE CELLS to release SECRETIN into THE BLOOD STREAM . This in turn causes…
The pancreas to release bicarbonate solution (which will neutralize the acidity of the chyme).
12. Proteins and fats in chyme also lead to a series of reactions. Describe them.
(Ex: proteins and fats in chyme causes the SMALL INTESTINE CELLS to release CCK into THE BLOOD
STREAM . This in turn causes…
The pancreas to release digestive enzymes (which will chemically digest the food in the chyme).
13. What processes are the liver involved in for your body to function?
● metabolizing carbohydrates, lipids, and proteins;
● storage of some substances (ex: glucose, amino acids);
● filtering the blood (ex: old RBCs);
● destroying toxins (ex: alcohol);
● producing bile.
14. How is the liver specifically involved in digestion? Produces bile
15. What is bile and what does it contain? Bile is the fluid produced by the liver and stored in the gallbladder; it
contains:
* bile salts
* bile pigments
* cholesterol
* electrolytes
16. What stimulates bile to enter the duodenum? Fats in food
17. What are the functions of bile salts? Emulsify fats (breaks big fat into smaller fats)
18. What does “emulsify” mean? Break into smaller pieces (ex: drinking glass is shattered into smaller shards of
glass if it is dropped)
19. What is the function of the gall bladder? Store bile until fatty foods enter the duodenum
20. What are gallstones? Crystalized cholesterol
21. What are the three divisions of the small intestine? Duodenum  jejunum  ileum
22. Where does the majority of chemical digestion occur? Small intestines
23. What is the function of villi? Increase surface area of small intestines
24. How do insulin and glucagon regulate plasma levels? (This should be a review for you!)
If blood glucose levels are too high, insulin is released. Insulin causes glucose in the blood to enter the cells of
the body so that it can be converted by the mitochondria into ATP energy. Excess glucose is converted to
glycogen which is then stored in the liver. Blood sugar returns to its set point. After time passes and the blood
glucose levels are too low, the hormone glucagon is released which causes the glycogen in the liver to be
converted back into individual glucose molecules and these are released into the blood stream. This increases
the amount of glucose in the blood back up to the set point.
25. What are the functions of the large intestine? Absorb water
26. Besides helping to protect against the colonization of pathogenic bacteria, what product made by the
intestinal flora (bacteria naturally found in your large intestine) is beneficial to your digestive system? vitamins
What product is unfortunate and annoying? gas
27. Describe the composition of feces.
-Water
-Electrolytes
-Bacteria
-Undigested material (ex: cellulose/fiber)
-Mucus
28. What causes:
 heartburn? Acidic chime entering the lower part of the esophagus (cardiac sphincter not closing
completely)
 diarrhea? Peristalsis is too fast so not enough water is being absorbed from the large intestines back into
the blood stream. As a result, too much water is in feces.
 constipation? Peristalsis is too slow so too much water is being absorbed from the large intestines back
into the blood stream. As a result, not enough water is in feces.
29. Fill in the following table:
Disease/condition
Salmonella poisoning
E. coli poisoning
Crohn’s (IBD)
Ulcerative colitis (IBD)
Colon cancer
Ulcer
Irritable Bowel Syndrome
(IBS)
Celiac Disease
Hemorrhoids
Diabetes Type 1
Diabetes Type 2
Appendicitis
Symptoms
See notes for symptoms
Cause
Bacteria in raw eggs, poultry, food left
out
Bacteria: usually in undercooked beef
but occasionally gets into agriculture
immune system attacks alimentary canal
immune system colon
Uncontrolled cell growth in colon
Bacteria causes open wound in stomach
or duodenum
Not sure but may be caused by too much
intestinal squeezing or too little
Immune system destroys villi of small
intestine
Swelling of anal veins
Immune system destroys cells in
pancreas that make insulin
Body no longer responds to insulin
properly (result of lifestyle)
Inflammation of appendix due to infection