Digestion

Question 1

Starch

Answer 1

a amylase cleaves 1,4
Isoamylase cleaves 1,6
Keeps teeth clean
Acts in mouth

Question 2

Lysozyme

Answer 2

cleaves 1,4 glycosidic bonds in bac cell wall

Gram+ bac killed by this enzyme

Question 3

Lingual Lipase

Answer 3

digests part of dietary fats

Question 4

HCl

Answer 4

antibac

Denatures proteins

Question 5

Pepsin

Answer 5

pH 2-2.5
produces oligopeptides
aromatic & large hydrophobic aa

Question 6

Gastric lipase

Answer 6

short FA & doesn’t need co lipase or bile acid

Question 7

Total Gastrectomy

Answer 7

Mild digestive problem (protein & fat can still get absorbed)
Risk for intestinal infection
Vit B 12 required (cobalamin)

Question 8

Pancreas

Answer 8

has bicarb to neturalize pH 
serine proteases:
- trypsin lys & arg COOH
- chymotrypsin hydrophobic aa COOH
- elastase small aa COOH

*also contains a amylaseP

Question 9

Carboxypeptidase A & B

Answer 9

A cleaves hydrophobic aa

B cleaves basic aa (lys & arg)

Question 10

Lipase

Answer 10

triglyceride= 2 monoacylglycerol & 2 FA
needs co lipase & bile acids

Only when touches lipid- water interface
Ser dep

Question 11

Phospholipases

Answer 11

cleave phospholiipds

Question 12

Nuclease

Answer 12

cleaves nucleic acids

Question 13

Pancreatic failure

Answer 13

steatorrhea & generalized lipid malabsorption

Risk of def of fat soluble vitamins!

Question 14

Intestinal FA binding protein

Answer 14

inside enterocyte FA binds to this enzyme

Re syn triacylglycerol in enterocyte & packed in lipoproteins to be released to lymphatics

Question 15

Liver & GB

Answer 15

bile salts needed for lipid digestion
Form mixed micelles which carry lipids to mucosal surface

Break up lipid/detergent micelles by peristalsis

W/o= steatorrhea
*bile stones

Question 16

Lipoproteins

Answer 16

Chylomicrons= transport food lipids & cholesterol from intestine through body
Lipoprotein lipase takes lipids away
Travel via lymphatics
Remnant released into blood & deliver cholesterol to liver.

VLDL, IDL, LDL= transport cholesterol & lipid from liver to otehr tissues

HDL= transport cholesterol & lipids from tissue to liver

Question 17

Fat malabsorption

Answer 17

No lipase/bile from pancreas/ GB

greasy, malodorous stools

Urine is dark

Question 18

Sugar proteins

Answer 18

Sucrase= sucrose into gluc & fructose
Lactase= lactose into gluc & galactose
Glucoamylase= glucose removed fro non red end of starch & maltose & oligosacch from starch
Trehalose= gluc & gluc type sugars

Question 19

Lactose Intolerance

Answer 19

Lactase drops after weaning

Milk/milk products have lactose which when undigested causes:
Flatulence
Abd pain
Diarrhea

Question 20

Pepsin

Answer 20

from pepsinogen
aa cleaved from amino end, catalyzed by pepsin or low pH
Cleaved peptide acts as pepsin I at neutral pH

Question 21

Trypsinogen

Answer 21

to trypsin by enteropeptidase in duodenum.
Trypsin activates all pancreatic zymogens (trypsinogen)
Trypsin inhibitor= small polypep binding to trypsin

Question 22

Acute pancreatitis

Answer 22

zymogens activated w/in pancreases spill into abd cavity & digest pancreas & adipose!

Find amylase & lipase in serum

Question 23

Chymotrypsinogen

Answer 23

Activation, change in protein structure

Question 24

Ethanol Detox in liver

Answer 24

Alc dehydrogenase in cytosol
Aldehyde dehydrogenase in mitochondria

Ethanol–> Acetaladehyde–> Acetic acid
2 NADH formed
enz 1- alc dehydrogenase
enz 2- aldehyde “

Question 25

Alcohol

Answer 25

Energy but no essential minerals, vitamins etc.
Increases fluidity of PM
Absorbed immediately
Produces ATP, NADH, H+, Acetyl co A
- inhibits glycolysis, B ox, Krebs
Acetyl co A converted to triglycerides= fatty liver
Gluconeogenesis inhibited by high NADH/NAD ratio!
Mitoch damage= leaky inner mem
Aldehyde cross & modify proteins!

Question 26

Alc detox

Answer 26

Aldehyde dehydrogenase variants= oriental flush acetylaldehyde accumulates

CYP450 metabolism, same as barbituates