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Flashcards in Biochem MUST remember Deck (78):
1

betaine

a metabolite that methylates stuff; has to do with choline

2

what are two types of fat with choline

phosphatydycholine
sphingomyelin

3

chylomicrons are secreted from? do what?

the intestines; transport TAG and dietary cholesteral to liver

4

want LDL or HDL?

HDL= happy=good

5

LDL does what? what is a disease when there is a difficiency?

its delivers cholesterol to cells that uptake it via receptor mediated endocytosis (if a cell needs cholesteral, LDL receptors are upregulated)
* familial hypercholesteremia if diffecient= low LDL and high blood cholesteral

6

what is bile salt?

steroid --.> cholic acid + glycine OR taurine = bile salt

7

two main types of bile salts?

glycocholic acid (with glycine)
tuarocholid acid (with taurine)

8

bile salts are made, stored and used where?

made in liver
stored in gallbladder
absorb FA in intestine

9

Malonyl CoA (3C)

* made from acetyl CoA + Co2
* FIRST mediator in FA synthesis
* regulates beta oxidation by inhibiting CARNITHINE ACYLTRANSFERASE 1
* acetyl CoA carboxylase is the biotin dependent regulated step in FA synthesis

10

acetyl CoA carboxylase

* acetyl CoA carboxylase is the biotin dependent regulated step in FA synthesis
* made from acetyl CoA + Co2 =Malonyl CoA (3C)
* allosteric enzyme
* turns on with high energy/citrate/acetyl CoA/insulin
*off with FA/palmitoyl CoA/epi/glucagon/low energy

11

FA sYnthesIs occurs where? beta oxidation occurs?

sYnthesIs= cYtosol and lIver
beta oxidation = mitochondira of liver and muscle

12

end product of FA synthesis?

Palmitate (16C)

13

CARNITHINE ACYLTRANSFERASE 1

transfers FA into liver for beta-oxidation/kreb cycle by removing TWO carbons at a time

14

3 ketone bodies

acetoacetate (CETO KETO) ---made into other two
D-B-Hydroxybutyrate ------shipped to brain
Acetone (cetone ketone)

15

ketone energy is used for?

the starved brain
*RBCs cannot use bc they have no mito

16

what is NOT a reducing sugar?

sucrose! (sucrose sucks!)
***but fructose by itself IS a reducing sugar, donates e-

17

what is regulator enzyme in ketone synthesis pathway?

HGM CoA synthase

18

amylose vs amylopectin

amylose is alpha 1,4 straight bonds only
amylopectin also has alpha 1,6 branched bonds (think you 'pek' bananas off a branch)

19

dextrans vs levans/fructans vs glycogen vs GAGs

dextrans= poly of glu made from sucrose
levans/fractans= poly of fractose made by sucrose
glycogen= poly of glu from glu
GAGs= chain of NEGATIVE disaccharides in ECM

20

strep mutans makes a glycocalyx capsule out of what?

mostly dextrans (but some levans)

21

6 main GAGs and what is unique

1) chondroitin sulfate - most abundant
2) hyaluronic acid -NO SULFUR
3) HEparin -ONLY INTRAcellular GAG; prevents formation of thrombin (mimics vit K deficiency) so it causes bleeding; has the MOST sulfate

4) heparin sulfate
5) dermatan sulfate
6) keratin sulfate

22

what two AA contribute to protein tertiary structure?

proline= turns/bends
cystaine= stabolize due to C=C bonds
OR cys to cysteine covalent sulfur bonds

23

most abundant protein by wieght? most abundant in serum

collagen= weight
albumin in blood serum

24

collagen composition? made where?

MOSTLY GLYCINE
* hydroxyproline and hydroxylysine; and alanine
* formed from hydroxylation of prolin and lysin
* procollagen (cytoplasm) to tropocollagen (ECM) to fibril to fibre

25

How does FA get into mitochondria for beta oxidation?

carnitine
CARNITHINE ACYLTRANSFERASE 1

26

How does acetyl CoA get from mito to cytosol for FA synthesis?

via the citrate shuttle

27

lysyl hydroxylase? what is its cofactor?

*enzyme that hydrolyzes (adds OH) to lysine and proline to form hydroxyproline and hydroxylysine to form collagen
*** vitamin C is cofactor, without it you'll get scruvy (poor wound healing, bleeding gums and lymes disease)

28

elastin is mostly made of? has no ____ bonds? has ___ crosslinks? high ___ strength? also has what NAME similar to tropocollagen?

mostly made of glcyine (like collagen)
no covalent bonds (bc stretchy)
has lysine crosslinks
high tensile strenght
tropoelastin

29

albumin maintains what type of pressure? what is oppoistie this pressure? found in what food?

maintains oncotic/colloid (PULL(
---opposite dyrostatic/blood pressure (push)
found in egg whites
simple prtein= ONLY AA found in it

30

amphipathic

hydrophilic andhydrophobic

31

plasma membranes made of?

1) lipids (phospholipids NOT tag) - most abundant
2) cholesterol
3) protein
4) carbs

32

what AA are found in proteins in plasma membrane?

leucine and valine bc non-polar and hydrophobic

33

what is in outer leaflet?

lecithins/sphingomyelin and ganglisides (lipids with sugar and NAM)

34

transferrin

transfers Fe when absorbed thru intestions!

35

cytochromes are composed of? found where?

protein _ heme + metal ion (Fe)
* found in INNER membrane of mito for ETC

36

facultative vs active similar?
different?

similar
* facilitated diffusion
* yes transporter
* yes competitive inhibition

different
* facultative =no energy; uses gradient
* active =ATP or +G and can be primary or secondary

37

GLUT 1 vs GLUT4

GLUT1= blood brain barrier
GLUT4= regulated by insulin for adipose and muscles (works in muscles, doesn't work=fat)

38

aspirin inhibits what, how?

inhibits COX1 and COx2 enzymes via suicide inhibition
(how penicillin works too)

39

what is Km?

velocity at 1/2 Vmax saturation!!!
**meaures in molarity!

40

trypsinogen

is a zymogen= enzymatically INactive PREcursor of proteolytic enzymes!
** can activate ALL pancreatic proteases
* converted into trypsin active form

41

isoelectric point vs zwitterion

isoelectric point= the pH at which a thing has NO net charge, its a pH value!
** a protein will MOVE until it reached iso point!

zwitterion= NET neutral molecules with a - and + charge
** zwitterion will NOT move

42

kinase vs phosphatase

kinase adds phosphates
phosphatases remove phosphates

43

alkaline phosphate and pyrophosphatase play a role in?

tooth calcification during development

44

feulgen stain?

differentiates between DNA and RNA by binding to deoxyribose in DNA

45

helicase
topoisomerase
SSBP
primase
DNA polymerase 3
ligase

helicase -unzips/separates
topoisomerase aka GYRASE -unwinds
SSBP (single stranded binding protein) -hold open
primase -tell DNA poly where to bind AND lay RNA primer
DNA polymerase 1- removes RNA primer
DNA polymerase 3 - builds new strand of DNA 3'-5'
ligase -glue, okazaki fragemnts

46

introns vs exons

INtrroverts leave party, EXtroverts stay

47

what 5 primary drugs inhibit TRANSLATION?

1) streptomycin
- bind to 30S
2) tatracycline
- bind to 30S, blocks tRNA at A site
- causes staining
3) clindamycin AND erythromycin
- bind to 50S
-antagonist to penicilin
4) aminoglycosides
- bind to 30S

48

DNA backbone bond?
sugar to base?
base to base?

DNA backbone bond? phosphodiester
sugar to base? glycosidic
base to base? hydrogen

49

what is Lesch-Nyan Syndrome?

juvenile gout caused by deficiency in HGPRT

50

if you have gout, what do you want to inhibit?

xanthine oxidase enzyme! because that is used to make uric acid ! (buildup of uric acid causes gout)

51

NADPH is made where?

pentose phosphate pathway!
*** along with ribose- 5 -phosphate

52

NADPH is used for?

1) FA synthesis
2) cholesteral/steroid synthesis
3)ribose/deoxyribose intercoversion
**NOT USED FOR GLUCONEOGENESIS********

53

flourouracil

suicide inhibitor of thymidylate synthase to disrupt pyrimidine synthesis

54

thymidylate synthase

enzyme needed to convert dUMP to dTMP to dTTP

55

R-5-phosphaste a result of what pathway?

pentose phosphate pathway
** along with NADPH

56

R-5-phosphaste is used to make?

1) ribose for nucleic acid synthesis
2) NADPH for FA and steroid synthesis

57

what do you get when you break down purines? what ENZYME does this?

uric acid
** xanthine oxidase enzymes!

58

HGPRT does what?

recycles purines! part of salvage pathway (instead of going to uric acid)
**causes Lesch-Nyan syndrome
**LesaH-HGPRT

59

what is SCID? caused by? what is AD?

severe combined immune difficiency caused by dfect in adenosine deaminase (AD) enzyme. AD used to break down purines!

think: SCID AD on TV wouldn't be PURE happiness

60

sulfonamine vs methotrexate?

sulfonamide
- looks like PABA
- compete to inhibit syn of folic acid which is needed for purine/pye synthesis

methotrexate
- used for cancers, incorporated in to DNA durin "s phase
- inhibits tetrafolic acid

61

what are B vitamins?

The thiamine B1
Rodeo riboflavin B2
Never Niacin B3
Puts Pantothenic Acid B5
Pansy Pyridoxine B6
Bulls Biotin B7
For Folic acid B9
Cowboys Cobalamine B12

62

glucose 6 phosphate dehydrogenase

- remember G6P is first step in PPP and glycolysis
-this is the enzyme that regulates G6P INTO PPP!!!!

63

oxidative vs non-oxidative phase of PPP

oxidative= NADPH
non-oxidative= ribose-5-P (nucleotides)

64

PPP occcurs where?

cytoplasm

65

urea cycle occurs where?

liver mitochondria

66

glyoxylate cycle

variation of Kreb's in platns/bacteria
* ANAPLEROTIC REACTION =replenishes it's own TCA intermediates
* acetate is main substrate!!!!!!

67

what is the rate limiting enzyme in Krebs?

isocitrate dehydrognase

68

what is the enzyme shared between ETC and TCA? what inhibits it? give an example of an isozyme?

succinate dehydrogenase
* malonate inhibits it
(different from malonyl CoA which inhibits beta oxidation!)

**isozyme = fumarate = 2 forms; urea cycle and Krebs

69

what is the most immediate source of OOA?

aspartic acid

70

what is the major enzyme in glycogenolysis?

glycogen phosphrylase

71

what is the emden-meyerhof pathway?

most common type of glycolysis!
* Net 2 ATP

72

what regulates the urea cycle?

carbomoyl phosphate synthetase

73

what are the 3 different nitrogen carriers?

1) glutamate
--- carries 1 amine group WITHIN liver cells (cannot leave)
2) glutamine
--- carries 2 amine groups BETWEEN cells
--- workhores, transfers most N thru blood
3) alanine
--- carries from the muscle

74

what vitamin is needed for 1st step in urea cycle?

PLP (B6) is a coenzyme fro aminotransferase

75

what are two sources of of N for urea cycle?

source 1: carbomoyl phosphate (NH4, ammonium)
source 2: ASpartATE (it ate ammoniA (NH3) and it tasted like ASS, so unload it)

76

what is direct precurser to urea?

arginine

77

what is the first step in urea cycle?

ornithine + carbomoyl phosphate = CITRULLINE (non-standard AA)

78

steps in urea cycle

ordinarily ornithine (non-standard AA)
careless carbomoyl phosphate (1st nitrogen source)
crappers citrulline (non-standard AA)
are aspartate (2nd nitrogen source)
always argininosuccinate
freaks fumarate
about arginine
urea urea