Brainscape's Knowledge GenomeTM

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


See full index

Bio 540 - Biochem > Exam 4 - Lipid Metabolism > Flashcards

Exam 4 - Lipid Metabolism Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What are the two most important tissues with respect to TAG production?

A

Liver and adipose

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

TAG is stored as lipid droplets in the []

A

cytoplasm

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

What “form” is TAG transported through the blood as?

A

Plasma-lipoprotein

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

Chylomicrons are a type of what….?

A

Plasma-lipoprotein

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

In a fasted states FA could be used for 2 things:

  1. Burned for energy to make []
  2. Used to make [] bodies
A
  1. glucose
  2. Ketone bodies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Acyl-CoA Synthetase does?

A

Activates fatty acids to acyl-CoA using ATP and CoASH

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

What primary intermediate do we need to get to in order to take Glyceraldehyde 3-Phosphate to TAG?

What 2 reactions take place to reach this intermediate?

A
  1. Lysophosphatidic Acid
  2. Reduction and Acylation
    1. Depends on the minor or major pathway for which one is first
    2. If Major pathway - reduction, followed by acylation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the path of “main” molecules from Glucose –> TAG?

A
  • Glucose –> Glyceraldehyde 3-P
  • Glyceraldehyde 3-P —> Glyceral 3-P
  • Glycerol 3-P —> Lysophosphatidic acid
  • Lysophosphatidic Acid —> Phosphatidic Acid
  • Phosphatidic Acid —> DAG
    • removal of a Pi
  • DAG —> TAG
    • Addition of Acyl group
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Glycerol 3-Phosphate acyl transferase does what?

A
  • Adds a Carbonyl/Acyl group to a glycerol 3-P molecule making the lysophosphatidic acid
    • Lyso means it only has 1 acyl group
    • The other group is an OH and the phosphate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What enzyme adds a second acyl group onto lysophosphatidic acids?

What would the product be?

A

Lysophosphatidic acid acyl transferase

Phosphatidic Acid

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

What acyltransferase acylates DHAP in TAG synth?

A

DHAP acyltransferase

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

What enzyme oxdizes acyldihydroxyacetone phosphate?

A
  • Psych
  • This enzyme reduces it - produces an NADP+
  • Acyldihydroxyacetone Phosphate reductase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What enzyme catalyzes the reaction of PA to DAG?

What “mechanism” does it use?

A

Phosphatidate phosphatase (or phosphatidic)

Hydrolyzes the phosphate

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

What enzyme catalyzes DAG —> TAG?

A

DAGAT

Diacylglycerate acyltransferase

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

What are all the acyltransferases in the Major and Minor Pathways of TAG synthesis?

A
  • Major
    • Glycerol 3-P acyltransferase
  • Minor
    • DHAP acyltransferase
  • Major and Minor - both meet at Lysophosphatidic Acid
    • Lysophosphatidic Acyltransferase
    • Diacylglycerate acyltransferase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the non acyltransferases in TAG synth?

A
  • Major
    • DHAP –> Glycerol 3-P…some sort of reductase
  • Minor
    • AcylDHAP Reductase
  • Both
    • Phosphatidic Phosphatase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

During fasting - does the body overcompensate by producing fatty acids form fat cells?

During fasting - glycerol production is [] via glycolytic intermediates, but requires [] …?

A

Yes

Not, Glyceroneogenesis

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

What are the 3 ways to utilize fatty acids for energy?

A
  1. Hydrolysis of Acyl groups from TAG
  2. Lipid Transport
  3. Deriving energy from fatty acids (B-Ox for example)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q
  1. Acyl groups hydrolysis from glycerol lipids is catalyzed by []
  2. [] are specfic for the lipid species and acyl position
  3. Adipose cells utilizes [] responsive lipases
  4. Any remaining glycerol is transported to the [] to be converted to []
A
  1. lipases
  2. Lipases
  3. hormone
  4. liver, DHAP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 3 types of lipids that are transported…and how is each transported?

A
  1. TAG
    1. PLP - plasma lipoproteins
  2. Fatty Acids
    1. Sereum Albumin (non covalent interactions)
  3. Ketone Bodies
    1. aqueous soluble…no transporter necessary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the 3 lipid transport pathways?

A
  1. Dietary Pathway
  2. Liver Pathway
  3. Fat Cell Pathway
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q
  1. Bulk of blood lipid is []
  2. [] bound fatty acids have the highest turnover rate
A
  1. TAG
  2. Albumin
23
Q

What are the 2 types of plama lipoproteins we covered?

A
  1. Chylomicrons
  2. VLDL - very low density lipoproteins
24
Q
  • Chylomicrons function in the [] in abosprtion and [] of dietary TAG, [] , and fat -soluble vitamins
  • VLDLS
    • synthesized in the []
    • Transports [] and [] to adipose tissue
      *
A
  1. intestine, transport, cholesterol
  2. Liver, TAG and fatty acids
25
Q
  1. What does Serum Albumin do?
  2. What are the 2 ketone bodies?
A
  1. hydrolysis of fatty acids from TAG in the blood
  2. Acetoacetate and B-hydoxybutyrate
26
Q

What are the 2 Ketone Bodies, and how is each made?

A
  1. Acetoacetic Acid
    1. Condense 2 acetic acids
  2. B-Hydoxybutyric Acid
    1. Reductino of acetoacetic Acid…..
27
Q

B-oxidation is [] -iterative process for [], []-numbered, [] chain fatty acids….

A
  1. 4 step
  2. saturated
  3. even numbered
  4. straight chain
28
Q

Why are fatty acids linked to ACP during B-oxidation?

A
  • Psych!
  • They are linked to CoA during B-oxidation!!
29
Q

What are the 4 “generic” steps of B-oxidation?

A
  1. Oxidation
  2. Hydration
  3. Oxidation
  4. Lysis
30
Q

Fatty Acids must be activated to the CoA ester by [] ??

A

Acyl CoA synthetase

31
Q

What molecule acts as a carrier of FA from the cytosl into the mitochondria?

What is the name of this system?

How many carbon-long chains does it normally transport?

A
  • Carnitine
  • Carnitine Palmital Transport
  • 12-18 Carbons
32
Q

Where is carnitine located as a transport molecule?

What is the negative effector of the carnitine transport system?

A
  • In between outer and inner mitochondrial membrane
  • Malonyl CoA
    • This is used to make FA - so of course it would be a negative effector of shit trying to break down FA like B-Ox
33
Q

What are the 4 enzymes used for normal B-ox?

A

Acyl-CoA dehydrogenase

Enoyl-CoA hydratase

Hydroxyacyl-CoA dehydrogenase

Ketoacyl-CoA thiolase

34
Q

How many ATP does Acyl CoA Synthetase require to active the acyl fatty acids?

A

2 ATP

35
Q

What does Acyl-CoA dehydrogenase do?

What are this enzymes products?

A
  • removes two electrons and forms and enoyl-CoA with trans double bond between the Alphat and Beta carbon
  • Products:
    • trans-delta2-Enoyl CoA
    • FADH2
36
Q

What does Enoyl-CoA hydratase do?

What are this enzymes products?

A
  • adds a water molecule across the trans double bond (lyase reaction) of trans-delta2-Enoyl-CoA… to generate a hydroxylacyl-CoA
    • Products:
      • 3-L-Hydroxyacyl-CoA
37
Q

What does Hydroxyacyl-CoA dehydrogenase do?

What are this enzymes products?

A
  • removes two electrons, reducing the hydroxyl group to a keto group
  • Produts:
    • B-Ketoacyl-CoA
    • NADH
38
Q

What does Ketoacyl-CoA thiolase do?

What are this enzymes products?

A
  • catalyzes the thioester cleavage and generates an acetyl-CoA and a fatty acid that is shorter by two carbons.
  • Products:
    • Acetyl-CoA
    • 2 carbon shorter FA
39
Q

Roughly, how many ATP does Acetyl-CoA get you through Krebs….

A

10 ATP

40
Q
  • Citrate and isocitrate act as [] regulators of ACCase through [] activation
  • C16 -C18 acyl CoAs act as [] regulators of ACCase through [] inhibition
A
  • Positive, allosteric
  • Negative allosteric
41
Q

How does insulin and glucagon effect ACCase?

A
  • Glucagon - inhibits it via PKA phosphorylation of ACC
  • Insulin - activation by dephosphorylation of ACC
42
Q

How many ATP are used to make palmitate and acetyl CoA?

A

42 ATP

43
Q

What are the differences in the steroechemical configurations of the B-hydroxy intermediats of Lipid Biosynth and B-Ox?

A
  • Biosynthesis
    • D
  • B-Ox
    • L
44
Q

Why does our normal Enoyl hydratase in B-Oxidation not work on unsaturated FA?

A

Becuase Enoyl hydratatse requires a trans double bond between the C2 and C3…however, unsaturated Fats have a cis double bond here.

45
Q
  • Enoyl-CoA isomerase* does what??
  • 2,4-dienoyl-CoA reductase* does what?
  • Enoyl-CoA isomerase* does what?
A
  1. converst a cis C3 double bond to a trans C2 double bond
  2. uses NADPH to produce trans C3 enoyl-CoA
  3. Converts the trans C3 enoyl-CoA to a trans C2 enoyl-CoA
46
Q

a-oxidation

  1. [] carbon elimination
  2. Requires a-carbon []
  3. Used to removes [] from branched chain FA
  4. Occurs in the [] , [] , and predominately the []
A
  1. 1 carbon
  2. hydroxylation
  3. branched
  4. mitochondria, ER, peroxisome
47
Q

What type of oxidation could yield a dicarboxylate?

A

w-oxidation

48
Q

Where is the primary site of Ketone Body Synth?

A

Liver

49
Q

What enzyme forms acetoacetyl-CoA by condensation reaction between two acetyl-CoA molecule in the mitochondria?

A

B-ketothiolase

50
Q

What is HMG-CoA Synthase’s function?

A

forms HMG-CoA by condensation reaction between acetoacetyl-CoA and acetyl-CoA

51
Q

What is HMG-CoA Lyase’s function?

A

cleaves HMG CoA into acetoacetate and Acetyl-CoA

52
Q

What enzyme uses NADH to reduce acetoacetate to B-hydroxybutyrate?

A

B-hydroxybutyrate dehydrogenase

53
Q

How many CoA’s are invested into the making of Ketone bodies…but how many are “actually” used?

A
  • 3 total are invest
  • 1 is remade though…so only 2 are used.
54
Q

What enzyme activates acetoacetate in muscle/brain cells in order to utilizes ketone bodies for energy?

A

3-oxoacid-CoA transferase

OR

Thioferase - This adds a CoA to acetoacetate!

Bio 540 - Biochem (14 decks)

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