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Year2 MSK exam 1 > Biochem > Flashcards

Flashcards in Biochem Deck (42)
1

functions of liver

maintain blood glucose
synthesize ketones from Acetyl CoA when switch to lipolysis
synthesize fatty acids, convert to TGs and release as VLDLs

2

requirements for liver

absorptive state: glucsoe and aa for energy
post-absorptive state: lactate, glycerol and aa for gluconeogenesis

3

functions of adipose tissue

take up fatty acids and convert to TG for long term storage
release FA into circulation

4

requirements for adipose tissue

glucose to produce glycerol phosphate for esterification of fatty acids
switch to fatty acids during post-absorptive

5

functions resting skel mm

release aa into blood

6

requirements for resting skel mm

absorptive state: glucose for oxidation and glycogen stores, aa for protein synthesis
post absorptive: fatty acids and ketones for energy

7

metabolism in fast twitch active skel mm

anaerobic glycolysis from glycogen

8

metabolism in slow twitch active skel mm

oxidative metabolism of glycogen
after several hours, switch to lipolysis

9

muscle contraction activates what metabolic pathway

TCA cycle
increase in Ca
increase in ADP
decrease in NADH and NAD+

10

what occurs in high intensity exercise

need for ATP exceeds mitochondrias capacity for oxidative phosphorylation

11

an increased NADH/NAD+ ratio directs what pathway

pyruvate into lactate

12

at intracellular pH what does lactic acid dissociate into

lactate and H+

13

decrease in pH causes what systemically

pain and fatigue

14

what is generated in low intesnsity exercise

glucose to CO2

15

increase in ADP stimulates what

isocitrate dehydrogenase
ETC to form NAD+ and FAD

16

decrease in NADH stimulates what

isocitrate dehydrogenase and malate dehydrogenase

17

increase Ca concentraiton causes what

stimualtes isocitrate dehydrogenase
stimulates alpha-ketoglutarate dehydrogenase

18

what happens when NADH/NAD ratio increases

citrate inhibits acetyl CoA entering TCA cycle
NAD+ is allowed to increase

19

what is rate limiting in aerobic metabolism

O2, the final electron acceptor

20

What TCA enzyme is in inner mitochondrial membrane and transfers electrons directly to CoQ within ETC

succinate dehydrogenase

21

what is the vitamin precursor of FAD

riboflavin

22

what is the vitamin precursor of NAD+

niacin

23

what is the vitamin precursor of CoA

pantothenate

24

increased transcription in myocytes leads to adaptive changes where

TCA cycle enzymes: increased #, decreased lactate production from pyruvate
ETC components: increased #
mitochondria: increased # size and productivity

25

increased vasodilatory capacity and lymphatic drainage from exercise can cause what metabolic changes

increased metabolites and decreased lactate

26

what will be increased in starvation

glucagon and epinephrine

27

what is main mech for metabolism in starvation

lipolysis to save proteins for essential functions
ACetyl CoA produced and converted to ketones

28

what does a muscle use for E in starvation

fatty acids

29

the brain uses what for E in starvation

ketones and glucose

30

what do RBCs use for E in starvation

glucose

31

when does amrnorrhea develop in response to dec body weight

when fat content is below 22% of normal
from reduced LH and FSH production

32

when does death by starvation occur

when 40% ideal body weight lost
30-50% body protein lost
70-95% body fat stores are lost

33

what decreases in starvation

depletion of muscly glycogen stores
depletion of adipose tissue TG
depletion blood glucose from liver glycogen

34

Sx vitamin deficiency

fatigue, nausea, loss of appetite
muscle pain from glycolysis as primary source of pain

35

what causes muscle pain in anorexic patient

glycolysis

36

whhat is riboflavin

vitamin precursor of FAD and FMN
major coenzyme in all tissues

37

niacin is a precursor to what

NAD+

38

niacin can be synthesized from what

tryptophan

39

what is required for alpha ketoglutarate dehydrogenase

thiamine

40

what is a precursor to CoA

pantothenate

41

what are Fe-S centers

in ETC, non-heme iron proteins that are affected by Fe deficiency anemia

42

what causes fatigue in iron deficiency anemia

the loss of Fe-S centers in ETC