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Flashcards in Biochem Deck (56):
1

type I collagen

most common (90%)
Bone
Skin
Tendon
dentin
fascia
cornea
late wound repair

defective in osteogenesis imperfecta

type I = bONE

2

type II collagen

Cartilage (including hyaline)
vitreous body
nuclear pulposus

type II = carTWOlage

3

type III collagen

Reticulin - skin, blood vessels, uterus, fetal tissue, granulation tissue

type III = defective in Ehlers-Danlos (threE D)

4

type IV collagen

basement membrane
basal lamina

type IV = under the FLOOR (BM)

defective in Alport synd

5

ApoA-I

LCAT activation (cholesterol esterification)
only in HDL

6

ApoB-48

chylomicron assembly and secretion by intestine to lymphatics
found in chylomicrons + remnants of chylomicrons

7

ApoB-100

LDL particle uptake by extrahepatic cells (BINDS LDL receptor)
found on VLDL, IDL, LDL

8

ApoC-II

LPL activation (cofactor for)
found on chylomicrons, VLDL, HDL

9

ApoE3 & E4

VLDL and chylomicron remnant uptake by liver cells
found on all, EXCEPT LDL!

10

vimentin

CT;
sarcomas

11

desmin

muscle;
rhabdomyosarcoma, leiomyosarcoma

12

cytokeratin

epithelial cells;
carcinomas

13

GFAP

neuroglia (astrocytes, schwann cells, etc.);
astrocytomas, glioblastomas

14

neurofilaments

axons w/in neurons;
neuroblastomas, primitive neuroectodermal tumors

15

peripherin

neurons

16

nuclear lamins (A,B,C)

nuclear envelope structural framework and DNA within

17

elastin contains which AA?

proline + glycine

18

enzymes that use B1 (thiamine) as cofactor

pyruvate dehydrogenase
alpha-ketoglutarate dehydrogenase
transketolase

19

rate limiting step in purine synth

glutamine PRPP amidotransferase

20

rate-limiting step in pyrimidine synth

CPS-II

21

needed to make pyrimidines

carbomyl phosphate (from ATP, CO2, glutamine)
aspartate

22

needed to make purines

glycine
aspartate
glutamine
THF
CO2

23

causes the positive charge of histones

lysine
arginine

24

causes the negative charge of DNA

phosphate groups

25

OTC deficiency vs orotic aciduria (Lab finding)?

OTC def - elevated serum ammonia
orotic aciduria - normal serum ammonia

26

eukaryotic DNA polymerase making own primer

alpha

27

eukaryotic DNA polymerase that replicates lagging strand

alpha

28

eukaryotic DNA polymerase that builds leading strand

delta

29

eukaryotic DNA polymerase that repairs DNA

beta

30

eukaryotic DNA polymerase that replicates mitochondrial DNA

gamma

31

prokaryotic DNA polymerase w/ 3'-->5' exonuclease activity

DNA polymerase III

32

function of 3'-->5' exonuclease

proofread - removes/replaces mismatched nucleotides

33

prokaryotic DNA polymerase w/ 5'-->3' exonuclease activity?

DNA polymerase I

34

function of 5'-->3' exonuclease

degrades RNA primer and replaces it w/ DNA

35

most abundant RNA

rRNA

36

longest RNA

mRNA

37

smallest RNA

tRNA

38

what makes rRNA in eukaryotes

RNA polymerase I

39

what makes mRNA in eukaryotes

RNA polymerase II

40

what makes tRNA in eukaryotes

RNA polymerase III

41

what provides the cap for mRNA

S-adenosyl-methionine (SAM)
7-methylguanosine cap

42

what is the polyadenylatin signal

AAUAAA

43

irreversible enzymes involved in gluconeogenesis

pyruvate carboxylase
PEP carboxykinase
fructose-1,6-bisphosphatase (rate-limiting)
glucose-6-phosphatase

44

rate-limiting enzyme of glycolysis

PFK-1

45

pyruvate dehydrogenase complex requires which 5 cofactors?

pyrophosphate (B1, thiamine; TPP)
Lipoic acid - inhib by arsenic (see: garlic breath)
CoA (B5, pantothenate)
FAD (B2, riboflavin)
NAD (B3, niacin)

"Tender Loving Care (TLC) For Nobody"

46

2 purely ketogenic AA

lysine
leucine

47

possible products of pyruvate

alanine
acetyl CoA
lactate
oxaloacetate

48

2 main nitrogen transporters in blood

alanine
glutamine

49

tissues that use pentose phosphate pathway

lactating mammary glands
liver
adrenal cortex
RBCs

50

BH4 (tetrahydrobiopterin) cofactor in synth of what?

serotonin
tyrosine
dopa
NO

51

4 functions of NADPH

1) synth FA and cholesterol
2) generate ROS
3) protect RBC from ROS damage
4) CYP450 enzymes

52

3 substrates that can undergo substrate level phoshorylation to create high-energy products (ATP or GTP)

-1,3-BPG
-PEP
-succinyl-CoA (makes GTP)

53

only step in glycolysis that makes NADH

glyceraldehyde-3-P --> 1,3-BPG

54

highest energy compound of glycolysis

PEP

55

in RBC, NADH needed to do what?

turn Met-Hb to Hb

56

breakdown of malate yields?

increased NADPH --> increased FA synthesis