Exam III – Chapter 41 – Worksheet 2
Chapter 41: Animal Nutrition (Part II)
1. What is the term used to describe the rhythmic waves of muscle contractions in the
esophagus?
 Peristalsis
2. Can you name and describe the four tissue layers found in the Esophagus, Stomach, and
Intestine?
 Mucusa – epithelial tissue (lines the lumen)
 Submucosa – connective tissue (blood vessels and nerves)
 Muscularis – smooth muscle (fibers run in all directions)
 Serosa – thin layer of connective and epithelial tissue (outermost)
3. What are the three main regions of the stomach?
 Cardiac – upper region
 Fundus – rounded area
 Pyloric – lower region
4. What type of glands line the lumen of the stomach and what is their role?
 Gastric Glands – located in the mucosa layer and secret gastric juice which aids
in enzymatic hydrolysis
5. What is gastric juice and which cells aid in its formation?
 Gastric Juice – mixture of pepsinogen and HCL
a) Chief Cells – secrete pepsinogen
b) Parietal Cells – secrete HCL
c) Mucus Cells – secrete mucus
6. Pepsinogen is a ___________, which when activated is called ____________.
 Zymogen (inactive enzyme); Pepsin
7. ____________ and ___________ activate pepsinogen.
 HCL; Pepsin
8. Can you name and describe the hormone that causes the release of gastric juice?
 Gastrin Hormone
 Made in the bottom of the stomach and affects upper stomach
 Stops production if stomach pH is too low (acidic)
9. What causes ulcers?
 Helicobacter pylori bacteria – live in the acidic environment of the stomach
10. Food enters the stomach as a ________ and exits as _________.
 Bolus; Chyme (semi-liquid dissolved food)
Exam III – Chapter 41 – Worksheet 2
11. The __________ of the intestine differs in animals due to their food source. Why?
 Size
 Plant material takes longer to digest
(Herbivores have longer intestines)
12. What are the three parts of the small intestine and what is their respective function?
 Duodenum – most digestion
 Jejunum – absorption
 Ileum – absorption
13. (T/F) The gall bladder makes bile which is then stored in the liver.
 False
14. (T/F) Bile contains digestive enzymes which aid in enzymatic hydrolysis.
 False
15. What is the function of Bile?
 Neutalizes chyme and breaks down fats
 Aids in absorption of fat (through the use of bile salts)
16. What is the function of Choleocytokinin (CCK)?
 Hormone that stimulates the release of enzymes from the pancreas and bile
from the gall bladder (both help to neutralize the chyme)
17. The hormone ________ stimulates the _____________ to release ______________ which
neutralizes chyme.
 Secretin; Pancreas; Sodium Bicarbonate (NaHCO3)
18. What do you think stimulates (signals) the production of Secretin?
 HCL in the chyme – too much HCL (acidic chyme) stimulates the need for
neutralization
19. CCK and ___________ inhibit ______________. Why?
 Secretin; Peristalsis
 Caused by chyme that is rich in fat and/or acidic.
 Allows time for the chyme to neutralize, enzymes to aid in digestion, and the
breakdown of fats before peristalsis moves it through the other parts of the
intestines.
Exam III – Chapter 41 – Worksheet 2
20. Which enzymes aid in carbohydrate digestion?
 Salivary Amylase (oral cavity) – Polysaccharides  smaller Polysaccharides,
Maltose
 Pancreatic Amylase (lumen of duodenum) – Polysaccharides  Maltose and
other Disaccharides
 Disaccharidases (epithelial layer of jejunum and ileum) – Disaccharides 
Monosaccharides
21. Which enzymes aid in protein digestion? Fill out table.
Enzyme (Origin)
Pepsinogen
(Stomach)
Trypsinogen
(Pancreas)
Chymotrypsinogen
(Pancreas)
Procarboxypeptidase
(Pancreas)
Activator
Active Form
HCL and
Pepsin
Pepsin
Enteropeptidase Trypsin
Trypsin
Chymotripsin
Trypsin
Carboxypeptidase
Endo/Exopeptidase
Endopeptidase
Exopeptidase
Aminopeptidase
Function
Cut
polypeptide
chain
internally
Cut
polypeptide
chain at
each end
22. Which enzymes aid in nucleic acid digestion?
 Pancreatic Nucleases (lumen of duodenum) – DNA and RNA  nucleotides
 Nucleotidases (epithelial layer of jejunum and ileum) – Nucleotides  Sugars,
Phosphates, and Nitrogenous bases
23. Which enzymes and salts aid in fat digestion?
 Bile Salts – Fat globules  Fat droplets
 Pancreatic Lipase – Fat droplets  Glycerol, fatty acids, and monoglycerides
24. (T/F) Everything except for fat is absorbed in the bloodstream.
 True
 Enters cell and incorporated into Chylomicrons
 Enters lacteal (lymphatic vessel in each villi)
25. What is the function of the Hepatic Portal System?
 Blood goes through 2 sets of capillaries (1 of 3 in the body)
 Functions to regulate distribution of nutrients to the rest of the body
 Allows for storage of excess sugars and amino acids in the liver (as glycogen)
 Allows the liver to remove toxic substances before the blood circulates
broadly
Exam III – Chapter 41 – Worksheet 2
26. What is the main function of the large intestine?
 Absorb and release water (most absorbed in the Small Intestine)
 Excrete salts (calcium and iron salts)