Midterm - Digestive System

Question 1

what are the 3 types of systems

Answer 1

1. simple system without caecum (human)
2. simple system with functional caecum (horse)
3. multiple system - ruminant (cow)

Question 2

what does the GI tract refer to

Answer 2

mouth
esophagus
stomach
small intestine
large intestine
caecum
rectum

Question 3

question for solubility

Answer 3

is a CHO soluble in the aqueous environment of the digestive tract?

Question 4

what is the digestibility question

Answer 4

does the host organism have the enzymes necessary to digest a CHO

Question 5

what is the fermentability question

Answer 5

do gut bacteria have the enzymes necessary to break down a CHO

Question 6

key features of simple system without caecum

Answer 6

monogastric
non functional caecum
hindgut fermenter
suited for nutrient dense low fibre diet

Question 7

what two enzymes are released from saliva

Answer 7

alpha-amylase and lingual lipase

Question 8

what volume is the stomach empty

Answer 8

50mL

Question 9

what volume is a filled stomach

Answer 9

1-1.5L

Question 10

how long does it take for gastric emptying

Answer 10

2-6 hours

Question 11

what is the pH of the stomach

Answer 11

~ 2

Question 12

what is in the gastric juice secreted by gastric glands

Answer 12

water
electrolytes
HCl
enzymes

Question 13

what is the main site for nutrient digestion and absorption

Answer 13

small intestine

Question 14

what is the surface area of the small intestine

Answer 14

30 m^2

Question 15

what is intestinal motility controlled by

Answer 15

longitudinal and circular muscles

Question 16

where does fermentation occur

Answer 16

large intestine

Question 17

where does water absorption occur

Answer 17

large intestine

Question 18

how many species of bacteria are identified per person in the gut

Answer 18

500-1000

Question 19

what is the ratio to anaerobic to aerobic bacteria

Answer 19

1000:1

Question 20

key features of a simple system with a function caecum

Answer 20

pseudo-ruminant
hindgut fermenter
functional caecum
all other regions very similar to monogastric
suited for a diet with large amounts of fodder and forgaing

Question 21

what is the purpose of a functional caecum

Answer 21

provides 70% of total energy needs for host

Question 22

what is the caecum a site for

Answer 22

vitamin production

Question 23

what are signs of an energy/nutrient deficiency

Answer 23

coprophagy

Question 24

key features of ruminant

Answer 24

foregut fermentation
4 compartments
suited for animals that eat high quantity of fodder and forage plant

Question 25

what are the 4 regions of the large stomach in a ruminant

Answer 25

reticulum
rumen
omasum
abomasum

Question 26

advantages of the ruminant system

Answer 26

vitamin synthesis
non-protein nitrogen used for making protein

Question 27

disadvantages of the ruminant system

Answer 27

carbs degraded into gases and lost through eructation
heat production

Question 28

digestibility

Answer 28

measure of the fraction of a specific nutrient/ energy that is extracted by the GI tract

Question 29

internal marker

Answer 29

a natural component of the feed

Question 30

external marker

Answer 30

a component added to the feed

Question 31

does apparent digestibility under estimate or overestimate true digestibility

Answer 31

under-estimates

Question 32

what is the difference between the GI tract and the digestive system

Answer 32

digestive SYSTEM refers to the GI tract AND associated organs (liver, pancreas, gallbladder)