Lecture 1-Whitfield

Question 1

what are the 7 organs of the GI tract?

Answer 1

1. mouth
2. esophagus
3. stomach
4. liver
5. pancreas
6. small intestine
7. large intestine (includes rectum and anus)

Question 2

what are the 4 ways by which GI tract is classified? describe

Answer 2

1. diet: carnivore, omnivore, herbivore
2. stomach: monogastric (dog, cat, pig, horse, people) or ruminant (cattle, sheep, goat, deer)
3. site of fermentation: forestomach (ruminants) or hindgut (horses, rabbit, rat, elephant)
4. differences: specialized anatomy or function

Question 3

describe the flow of feed generally in most animals

Answer 3

1. mouth
2. esophagus
3. stomach (+ forestomach for ruminants)
4. small intestine: duodenum, jejunum, ileum
5. large intestine: cecum, ascending colon, transverse colon, descending colon, rectum, anus

Question 4

what is prehension?

Answer 4

the seizing and conveying of food into the mouth

Question 5

give the prehensile organs of
people, dogs, horses, cattle, goats, and seahorses

Answer 5

people: hands
dogs: mouth
horses: lips
cattle: tongue
goats: lips
seahorses: tail

Question 6

why are there species differences in salivary glands?

Answer 6

there are different levels of moisture in diets (ex. cows have a lot of saliva because hay is very dry but dogs (carnivores) don’t have as much saliva because fresh dead meat has more moisture

Question 7

what is the purpose of the stomach in monogastrics?

Answer 7

acidic breakdown and enzymatic breakdown (forestomach in ruminants has more functions but more on that later)

Question 8

what are the 3 functions of the small intestine? describe its level of species difference

Answer 8

1. enzymatic digestion
2. absorption
3. immune functions
   the small intestine is the most similar among species

Question 9

what are the 2 general functions of the large intestine? describe its level of species difference

Answer 9

1. fermentation
2. water absorption
   highly specialized among species

Question 10

what are the 2 functions of the rectum and anus?

Answer 10

1. store feces (additional water absorption)
2. provide a seal against the outside