Gi 8-17 Digestion And Absorption Of Proteins And Carbs

Front 1

what are the sevendietary carbohydrates include

Back 1

starch(amylose and amylopectin), glycogen, isomaltose, maltose, lactose, sucrose and cellulose

Front 2

why is cellulose not digested

Back 2

because it contains B-1,4 glycosidic bonds),

Front 3

what are the bonds of the other dietary carbs that are digested

Back 3

alpha1,4 and alpha1,6 glycosidic bonds

Front 4

where does carbohydrate digestion begin?
what enzyme

Back 4

the mouth alpha-amylase(ptyalin)

Front 5

where is alhpa amylase active and what does it break down

Back 5

near neutral pH, and breaks long oligosaccharides into shorter chains and disaccharides

Front 6

what digests carbs in the stomach

Back 6

digestion stops in the stomach b/c the low pH inactivates the alpha amylase

Front 7

what aids in carb digestion and is added to chyme whenit reaches the duodenum

Back 7

pancreatic alpha-amylase

Front 8

what are the resulting products of pancreatic a-amylase

Back 8

disaccharides
maltose
sucrose and
lactose

Front 9

can disaccharide be absorbed?

Back 9

no

Front 10

where do the the enzymes come from that catabolize disaccharides?

Back 10

on the luminal membranes of enterocytes

Front 11

name the enzymes that break down the disaccharides on enterocytes

Back 11

glucoamylase (maltase)
lactase
sucrase

Front 12

what are the percentage of monosacs that are transported into the blood

Back 12

80% glucose, 10% frctose and 10% galactose

Front 13

how does glucose and galactose cross the enterocyte cell membrane

Back 13

via sodium-dependent transporters

Front 14

the hexoses are transported across the abluminal membrane of the enterocyte and into the?

Back 14

hepaatic portal circulation
also Na+ dependent

Front 15

stoped at protein digestion and absorption

Back 15

k

Front 16

how much protein do we digest a day

Back 16

70-100gm
2x the amount needed to replace amino acids

Front 17

where are the proteases secreted by which accomplish the digestion of protein

Back 17

stomach, pancreas, and small intestines

Front 18

what gartic secretion aids in catab of protein

Back 18

pepsinogen

Front 19

what does pepsin primarily produce

Back 19

short chian polypeptides and some aminocids

Front 20

what does the pancreas secrete that aids in catab of protein

Back 20

inactive proteolytic precursors (trypsinogen, chymotrypsinogen, procarboxypeptides, proelastase

Front 21

the zymogens of the pancreas are converted to there active form by?

Back 21

the secretion of enterocytes, a proteolytic enzyme called enterokinase (or enteropeptidase

Front 22

what does the enterokinase convert?

Back 22

trypsinogen to trypsin and the trypsin does the rest of the activation

Front 23

the actions of what four enzymes take the shorter length poplypeptides and oligopeptides (short chains

Back 23

trypsin, chymotrypsin, carboxypeptidease and elastase

Front 24

enterocytes also express a proteolytic enzyme of their own called?

Back 24

aminopeptidase

Front 25

what is the fun't of aminopeptidase

Back 25

clips off single a.a. form the N-terminal of oligopeptides and eventually yields single a.a. and di and tripeptides

Front 26

the a.a. di and tri peptides are transported into? by?

Back 26

enterocytes by a fmaily of at least sodium-dependent a.a. transporters

Front 27

what happens to the di or tripeptides once inside the enterocytes

Back 27

are broken down into single a.a. by intracellualr peptidases

Front 28

what? are transported across the abluminal membrane into what?

Back 28

only a.a
hepatic portal circulation