digestion and absorption

Question 1

main organ of digestion and absorption

Answer 1

small intestine

Question 2

how much ml os lost each day in the stool?

Answer 2

100ml

Question 3

are invaginations of the epithelium between the vili and are lined largely with younger epithelial cells

Answer 3

crypts

Question 4

peptidases

Answer 4

cleave peptides to amino acids

Question 5

enterocyte process and transport (4)

Answer 5

1. aa
2. glucose
3. monoglycerides
4. membrane enzymes

Question 6

enteric endocrine cell involved with (3)

Answer 6

1. gastrin
2. cck
3. secretin

Question 7

paneth cell release

Answer 7

lysozyme which protects against bacterial infections

Question 8

surface area of small intestine

Answer 8

largeeeeeeee due to the microvilli approx. the size of half of a basketball court

Question 9

area where partially digested food from the stomach (chyme) is mixed with bile and pancreatic enzyme

Answer 9

duodenum

Question 10

area where the chyme undergoes the largest amount of digestion with significant amount of nutrient absorption

Answer 10

jejunum

Question 11

are where large amounts of nutrients are absorbed before emptying into the large intestine

Answer 11

ileum

Question 12

mainly involved in the absorption of water and salts from the material that has not be digested. most digestion and nutrient absorption has already taken place

Answer 12

colon

Question 13

most absorption of nutrients occurs along the entire small intestine with the exception of (3)

Answer 13

1. iron- duodenum
2. vit. B12- ileum
3. Bile salts- ileum

Question 14

in general, the digestive system is set up to maximize absorption; there is no regulation in the amount of substance absorbed into the body

Answer 14

yep

Question 15

products of digestion are absorbed through the GI tract by (3)

Answer 15

1. simple diffusion
2. carrier method
3. channel mediated

Question 16

products of digestion goes to the vasculature/lymphatics

Answer 16

vasculature

Question 17

glucose, lactose and fructose transporters

Answer 17

glucose and lactose are transported by a Na+ dependent transported. Fructose uses a non-Na+ dependent transporter

Question 18

enterokinase

Answer 18

cleaves trypsinogen

Question 19

why are there are so many pancreatic proteases?

Answer 19

proteases cleave at specific a.a sites

Question 20

there are different transport aa into the enterocytes but the most common is the

Answer 20

sodium dependent co-transporter

Question 21

dietary fats are _____ that form micelles through pancreatic lipase to penetrate the unstirred layer adjacent to the small intestine epithelium and to be absorbed

Answer 21

triglycerides

Question 22

of particular importance in fat digestion and absorption are _____ which emulsify the fats allowing for their solution as micelles in chyme and increase/decrease the surface area on which the pancreatic lipases can operate

Answer 22

of particular importance in fat digestion and absorption are bile salts which emulsify the fats allowing for their solution as micelles in chyme and increase the surface area on which the pancreatic lipases can operate

Question 23

triglycerides enter the smooth endoplasmic reticulum where they are repackaged into ________ and then secreted into the vasculatures/lymphatics

Answer 23

triglycerides enter the smooth endoplasmic reticulum where they are repackaged into chylomicrons and then secreted into the lymphatics

Question 24

amount of water transported by each colon epithelial cells is much larger than that of the small intestinal cell

Answer 24

yep

Question 25

absorption of aa/simple sugars vs fatty acids/ glycerol

Answer 25

aa/ simple sugars are absorbed through membrane channels or transported while fatty acids and glycerol are absorbed directly

Question 26

of all the digestive enzymes only stomach and pancreatic proteases need to be

Answer 26

activated

Question 27

all the intestinal digestive enzymes are bound how?

Answer 27

membrane bound to the enterocyte apical membrane