Biochem review

Question 1

liver fnxs

Answer 1

maintain blood glucose
synthesize ketones form Acetyl-CoA during lipolysis
synthesize FAs and converts to TGLs and release as VLDLs

Question 2

requirements for liver fnx

Answer 2

absorptive state: glucose and AA for energy

post-absorptive state: lactate, glycerol, and AA for gluconeogenesis

Question 3

adipose fnxs

Answer 3

take up FAs and convert to TGLs for storage

release FAs into circulation

Question 4

requirements for adipose fnx

Answer 4

glucose to produce glycerol phosphate for esterification of FAs
switch to FAs during post-absorptive state

Question 5

resting skeletal mm fnxs

Answer 5

release AAs into blood

Question 6

requirements for resting skeletal mm fnx

Answer 6

absorptive state: glucose for oxidation and glycogen stores, AAs for protein synthesis
post-absorptive state: FAs and ketones for energy

Question 7

active skeletal mm fnx

Answer 7

fast-twitch: anaerobic glycolysis from mm glycogen (primary source of energy)
slow-twitch: oxidative metabolism of glycogen
after several hrs switch to lipolysis

Question 8

immediate changes after meal

Answer 8

BG increases followed by increase in TGs and AAs

Question 9

increased BG detected by what

Answer 9

pancreas -> releases insulin

Question 10

insulin effects on liver and mm

Answer 10

glycogen synthesis increases until maxed then FA production increases
protein synthesis increases in mm

Question 11

insulin effects on adipose

Answer 11

TGs synthesis

Question 12

insulin effects on brain and red cells

Answer 12

nothing

Question 13

what occurs in post-absorptive/fasting state?

Answer 13

glucagon released

epi increases

Question 14

glucagon on liver

Answer 14

glycogenolysis
glucose released in blood
AA and FAs into liver for gluconeogenesis

Question 15

epi on mm

Answer 15

AA released into blood

Question 16

epi on adipose

Answer 16

FAs released into blood

Question 17

how does mm contraction activate TCA cycle?

Answer 17

increased Ca
increased ADP
decrease in NADH/NAD ratio

Question 18

does NADH dehydrogenase activity increase or decrease in exercise

Answer 18

increase b/c using NADH in ETC

Question 19

what happens to lactate dehydrogenase in exercise

Answer 19

increases bc converting pyruvate -> lactate

Question 20

what happens to the ATP:ADP ratio in exercise

Answer 20

decreases

Question 21

what happens to NADH:NAD ration in intense anaerobic exercise?

Answer 21

increased

Question 22

anaerobic mm metabolism

Answer 22

high intensity exercise
ATP need > mito capacity for ox phos
increased lactate production (increased NADH:NAD ratio directs pyruvate-> lactate)
Increased H productin (lactic acid dissociates -> decreased pH -> pain and fatigue)

Question 23

aerobic metabolism

Answer 23

low intensity exercise
rate of ATP utilization lower and ox phos sufficent
increased CO2

Question 24

how does exercise increase ATP utilization

Answer 24

increased TCA cycle

increased ETC

Question 25

increased TCA cycle

Answer 25

generates NADH and FADH2 which are required for and drive ETC

Question 26

increased ETC

Answer 26

generates ETC and FAD which are required for and drive TCA

Question 27

increased ADP

Answer 27

- stimulates isocitrate dehydrogenase in TCA | - stimulates ETC to form NAD and FAD

Question 28

isocitrate dehydrogenase

Answer 28

isocitate -> alphaketo-gluterate | rate limiting enzyme

Question 29

ETC utilizes NADH

Answer 29

decrease in NADH stimulates: -isocitrate dehydrogenase -malate dehydrogenase (NADH inhibits these)

Question 30

decreases O2

Answer 30

halts ETC -> increases NADH > inhibits TCA cycle

Question 31

increased Ca

Answer 31

stimulates: - isocitrate dehydrogenase - alpha-ketoglutarate dehydrogenase

Question 32

alpha-ketogluterate dehydrogenase

Answer 32

alpha-ketogluterate -> succinyl CoA

Question 33

malate dehydrogenase

Answer 33

malate -> oxaloacetate

Question 34

when NADH/NAH ratio increases

Answer 34

build up of citrate -> inhibits Acetyl CoA entering TCA and NAD begins to build up again

Question 35

changes that occur with exercise over time

Answer 35

increased number of TCA cycle enzymes and decreased lactate production from pyruvate increased number of ETC components increased mito increased vasodilatory capactiy and increased lymph drainage

Question 36

starvation

Answer 36

glucagon and epi markedly increased -> glycogenolysis and lipolysis

Question 37

amenorrhea

Answer 37

when body fat <22% of body weight | due to decreased LH and FSH production

Question 38

symptoms of vit deficiency

Answer 38

non-specific fatigue, nausea, loss of appetite mm pain d/t glycolysis as primary energy source b/c lacking co-enzymes for metabolism

Question 39

riboflavin

Answer 39

precursor for FAD and FMN needed for ETC | widely distributed in foods turn over slow, onset slow

Question 40

niacin

Answer 40

vit precursor for NAD | can be synthesized from tryptophan so deficiency rare

Question 41

thiamine

Answer 41

required for alpha-ketodehydrogenase of TCA

Question 42

pantothenate

Answer 42

precursor for CoA | widely distributed in foods

Question 43

Fe deficiency and ETC

Answer 43

need non-heme Fe for ETC | decrease in Fe-sulfur center -> lose gradient for e transport