Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biochemistry > BB451 exam 2 - Fatty Acid Metabolism > Flashcards

BB451 exam 2 - Fatty Acid Metabolism Flashcards

1
Q

fats stored in

A

adipocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

fatty acids travel in blood stream by…

A

serum albumin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

degradation (summary)

A

in mitochondria and peroxisome

oxidation, hydration, oxidation, cleavage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

synthesis (summary)

A

in cytoplasm and ER and mitochondrion

reduction, dehydration, reduction, condensation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

lipases

A

break down fats to fatty acids and glycerol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

glycerol

A

only part of fat that can be made into glucose (via gluconeogenesis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

across intestine wall…

A

monoacylglycerol + fatty acids –> across wall

then reassembled and go to chylomicrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

triacylglycerol lipase

A

hormone sensitive
only regulated enzyme of fat or fatty acid breakdown
in adipocytes
cute first one off?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

oxidation in mitochondrial matrix

A

in cells: fatty acids attached to CoA (acyl-CoA)
at mitochondria: CoA replaced by carnitine
in matrix: carnitine replaced by CoA again

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

steps in beta oxidation mirror…

A

oxidation of succinate to oxaloacetate in CAS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

step 1 beta oxidation

A

dehydrogenation

enzyme: acyl-CoA dehydrogenases
- -> FADH2 and intermediate w/ double bond in trans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

step 2 beta oxidation

A

hydration: add water across double bond

- -> hydroxyl group on 3rd C from CoA in L form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

step 3 beta oxidation

A

oxidation –> NADH and ketone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

step 4 beta oxidation

A

thiolytic cleavage

catalyzed by thiolase : cleave off acetyl CoA –> fatty acyl-CoA with 2 fewer Cs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

thiolase

A

catalyzes thiolytic cleavage (step 4 in beta oxidation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

acyl-CoA dehydrogenase

A 
catalyzes dehydrogenation (step 1 in beta oxidation) 
specialized form for long, medium, and short chain fatty acids 
pulls out protons and e's between C2-3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

short and medium chain acyl-CoA dehydrogenases ….

A

in mitochondria
short : 8-10 or smaller
medium - some instances of sudden infant death syndrome if deficient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

long chain acyl-CoA dehydrogenases

A 
in peroxisomes (>16C)
e to oxygen --> hydrogen peroxide instead of FADH2 (less efficient)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

most common fatty acid

A

palmitic acid / palmitoyl - CoA
16 carbons
cycle 7 times –> 8 acetyl CoAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

enoyl -CoA - isomerase

A

converts cis (or trans) bonds between 3-4 to trans between 2-3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

beta oxidation normally has ___ bonded intermediates between __

A

trans bonds intermediates between 2-3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

2,4 - dienoyl - CoA reductase

A

acts on intermediates that have double bonds between 2-3 and 4-5.
uses NADPH to reduce 2 double bonds to 1 in cis between 3-4
the enoyl-CoA isomerase can act

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

oxidation of fatty acids with odd number of carbons

A

propionyl - CoA (3 carbons) (not acetyl-CoA)

propionyl CoA –> succinyl CoA requires enzyme that uses coenzyme B12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

steps in oxidation of fatty acids with odd number of carbons

A

addition of carboxyl to middle carbon, 2 unusual isomerizations and movement of methyl group that uses cobalt atom of B12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

ketone bodies

A

produced when glucose precursors are not available to make glucose
ex: acetoacetate and hydroxybutyrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

sign of diabetic..

A

acetone on breath

acetoacetate unstable –> acetone, very volatile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

thiolase

A

thiolase reaction in ketone body formation is reversal of same reaction in fatty acid metabolism (between oxidation and synthesis)

28
Q

synthesis up to palmitate occurs in…

A

cytoplasm

29
Q

fatty acids built using

A

acyl carrier proteins (ACP)

30
Q

___ used to donate e’s in synthesis

A

NADPH

31
Q

malonyl-ACP…

A

3 carbons
donated 2 Cs to growing fatty acid chain
CO2 lost in process

32
Q

synthesis of fatty acids longer than ____ occur in___

A

longer than 16C occur in ER or mitochondria

33
Q

in synthesis, a ___ intermediate is formed at ___

A

a D-hydroxyl intermediate is formed at C3

34
Q

beta oxidation occurs in

A

mitochondrial matrix

35
Q

beta oxidation uses ___

A

CoA

36
Q

___ used to accept e’s in oxidation

A

NAD and FAD

37
Q

beta oxidation yield

A

2 carbon acetyl - CoA units

38
Q

oxidation of fatty acids longer than ___ occurs on ___

A

longer than 16 in peroxisome

39
Q

in oxidation and __ intermediates is formed at ___

A

L-hydroxyl intermediate at C3

40
Q

acetyl - CoA carboxylase

A

addition of carboxyl group to acetyl CoA –> malonyl coA (3C)

41
Q

regulation of acetyl-CoA carboxylase

A

alloserically - inhibited by palmitoyl-CoA (first end product, feedback inhibition), activated by citrate

covalent modification - phosphorylation inhibits

42
Q

CoA from malonyl-CoA swapped for …

A

swapped for ACP to start synthesis –> malonyl-ACP

43
Q

acetyl-CoA gets into cytoplasm from mitochondria by….

A

citrate shuttle
acetyl-CoA linked to oxaloacetate in mitochondria –> citrate –>transported out –> citrate cleaved –> acetyl CoA + oxaloacetate in cytoplasm

44
Q

only enzyme regulated in synthesis

A

acetyl CoA carboxylase

45
Q

malonyl ACP is…

A

adding block for synthesis

46
Q

acetyl ACP is …

A

starting block

47
Q

decarboxylation of malonyl ACP –>

A

2 carbon addition to growing chain (onto carboxyl end)

48
Q

1st reaction in saturated fatty acid synthesis

A

malonyl ACP + acetyl ACP

condensation - CO2 lost (CO2 on then off…)

49
Q

saturated fatty acid synthesis ….

A

malonyl ACP + acetyl ACP
reduce - use NADPH –> alcohol
dehydration –> trans double bond
reduction - use NADPH –> 4C fatty acid (combine with new malonyl - ACP)
continues until 16 carbons (palmitoyl - CoA)

50
Q

fatty acid synthase

A

multi enzyme complex
catalyzes all reaction up to 16 carbons
rotates through reactions like clock

51
Q

desaturases

A

produce unsaturated fatty acids
in ER
use unusual e transferring initiated by donation of e from NADH to oxygen

52
Q

essential fatty acids

A

must be in diet, cant make
in animals: linoleic and linolenic acids
cant make double bond past delta - 9

53
Q

fatty acids longer than 16 produced by…

A

elongases - 2 carbons at a time

in ER and mitochondria

54
Q

trans fatty acids produced by

A

partial hydrogenation of vegetable oil

55
Q

prostaglandins

A

hormone like compounds made from arachidonic acid by prostaglandin synthase

56
Q

prostaglandin synthase

A

many in body

reactions are forming cyclic oxygen containing compounds –> cyclooxygenases (COX)

57
Q

prostaglandin effects

A 
vasoconstriction/dilation 
uterine contractions
aggregation/stickiness of platelets 
inflammation/pain 
maintenance of stomach lining
58
Q

linoleic acid released from ___ by ___

A

released from glycerophospholipids by PLA2

59
Q

PLA2 inhibited by

A

corticosteroids

treat sever inflammation/pain

60
Q

linoleic acid—>

A

arachidonic acid

61
Q

leukotrienes

A

from arachidonic acid via linear pathway
mucus production and bronchial constriction
cause asthma attacks and allergies

62
Q

cyclic pathway from arachidonic acid

A

prostaglandins –> thromboxanes

63
Q

thromboxanes

A

help make platelets sticky favoring aggregation

64
Q

asprin and blood clotting

A

reduce synthesis of prostaglandins –> reduce thromboxanes –> reduce stickiness of platelets

65
Q

prostaglandins get out of cell by

A

multi drug resistance protein

66
Q

prostaglandins are a ___ hormone

A

local - only effects in location synthesized

Biochemistry (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions