review session questions Flashcards Preview

biochem block 1 > review session questions > Flashcards

Flashcards in review session questions Deck (38):
1

intermediate common to the catabolism of carbs, fat, protein

acetyl-CoA

2

ketone synthesis occurs only in the-

liver

3

largest energy store in the body

TAG in adipocytes

4

RQ equation

RQ = CO2/O2

5

free fatty acids are liberated from chylomicrons and VLDL by-

lipase

6

glycogen will accumulate in the liver until is is what % of total weight of liver

5%, beyond that = glycogen storage dz

7

inputs for gluconeogenesis- 3

lactate from glycolysis
aa (alanine and glutamine) from mm breakdown
glycerol from TAG breakdown

8

when will gluconeogenesis typically begin

after an overnight fast

9

what tissue initially uses ketones for energy

initially used by mm, once levels increase sufficiently, will be used by the brain

10

aa used as buffer in the kidney

glutamine

11

sites of gluconeogenesis

liver and kidney

12

preferred mm fuel with high intensity exercise

glucose/glycogen

13

preferred mm fuel with sustained exercise

fat

14

MOA of cortisol

effects gene expression, long term regulator, increases glycogen synthesis

15

insulin receptor type

tyrosine kinase receptor

16

glucose receptors on brain

GLUT1, GLUT3

17

glucose receptors on RBC

GLUT3

18

catalysts work by-

decreasing activation energy, increase rate, stabilize the transition state

19

catalysts cannot-

change equilibrium

20

special characteristics of enzyme catalyzed runs

physiologic conditions, highly efficient, highly specific, regulation, targets for drugs

21

thyamine pyrophosphate (B1)

aldehyde transfer

22

Pyridoxal phosphate (B6)

group transfer to/from amino acid

23

biotin

activates/transfers CO2

24

coenzyme A

transfer of acyl group or thiol ester

25

function of asp in serine protease active site

asp pulls H from His to activate it

26

describe the problem when G6PD is mutated

mutation in G6PD makes it less temperature stable, decreased stability decreases product concentration (NADPH), decreased NADPH = decreased GSH = accumulation of free radicals

27

when are the effects of G6PD mutation more evident?

fever, oxidative stress

28

what activates trypsinogen to trypsin?

enteropeptidase

29

michaelis-menton equation

v = vmax / 1+ (km/[S])

30

when km = [S], v=

1/2 vmax

31

hexokinase has lower km meaning it has...

increased activity at lower substrate concentrations

32

DR x intercept

x int = -1/km

33

DR y intercept

y int = 1/Vmax

34

DR slope

slope = km/vmax

35

effect on KM and vmax competitive inhibitors

increase Km
Vmax unchanged

36

effect on KM and vmax noncompetitive inhibitors

Km unchanged
decrease vmax

37

structure of inactive PKA

2 regulatory and 2 catalytic subunits, regulators act as pseudo substrate

38

calmodulin activates enzymes by

binding their pseudo substrates and reversing auto inhibition