Lipid Metabolism

Question 1

What do lipids do?

Answer 1

Storage for fuel
Structural components
Participate in signal transduction
Provide with insulation, creates heat and fat digestion

Question 2

Source of Fatty Acid synthesis is

Answer 2

Dietary carbs. Not F.A because that would suppress synthesis.

Question 3

Describe the 3 phases of Fatty Acid Synthesis

Answer 3

Phase 1: Cytosolic entry to acetyl coa

Phase 2: Generation of Malonyl Coa

Phase 3: Fatty acid chain formation

Question 4

What is special of Malonyl Coa?

Answer 4

Its a substrate for F.A synthase but also a regulator that inhibits F.A degradation.

Question 5

Rate limiting step of F.A synthesis

Answer 5

Acetyl Coa Carboxylase

Question 6

Fatty Acid Synthase structure

Answer 6

Multi enzyme complex with two identical dimers. Each dimer has identical 7 enzymes with a special ACP: Acyl carrier protein

Question 7

Phase 3 of F.A synthesis reaction:

Answer 7

1 acetyl coa + 7 malonyl coa + 14 NADPH = Palimitate + 14 NADP + 8 coa

Question 8

Elongation of F.A is completed in what organelle?

Answer 8

Smooth endoplasmic reticulum (2 carbons at a time)

Question 9

Unsaturated or double bonds can not be added beyond carbons #__ and #__ in F.A

Answer 9

9 or 10

Question 10

Omega 6 F.A

Answer 10

Linoleic acid

Question 11

Omega 3 F.A

Answer 11

Linolenic acid

Question 12

Linoleic acid makes

Answer 12

Arachidonic acid

Question 13

Linolenic acid makes

Answer 13

EPA and DHA

Question 14

What are the 4 lipases of TAG breakdown?

Answer 14

ATGL
HSL
LPL
MAG

Question 15

What activates TAG breakdown?

Answer 15

Glucagon or Epinephrine

Question 16

4 Enzymes of Carnintine shuttle

Answer 16

Fatty Acyl CoA Synthetase

Carnitine palmitoyltransferase

Carnitine acylcarnintine translocase

Carnitine palmitoyltransferase II

Question 17

Name major type of ACAD

Answer 17

Medium chain Acyl Coa Dehydrogenase

Question 18

What is the most important enzyme of B oxidation?

Answer 18

ACAD: Acyl Coa Dehydrogenase

Question 19

Metabolic defects of fatty acid oxidation stems from two notable pieces of the process?

Answer 19

Carnitine shuttle

ACAD

Question 20

MCAD Deficiency

Answer 20

Cant break down MCFA

Need a lot of glucose in diet

Question 21

Ketone bodies

Answer 21

Acidic and water soluble

Occurs when body is not undergoing any glucose metabolism esp when not eating glucose. Releasing lots of FA

Question 22

What are the 3 ketone bodies?

Answer 22

Acetoacetate
B-Hydrobutyrate
Acetone

Question 23

Where are ketone bodies produced?

Answer 23

Liver but specifically in mito matrix. Provides energy to brain during starvation, muscles when fasting and kidneys.

Question 24

Difference between physiological ketosis and pathological acidosis

Answer 24

Physio is mild to moderate to increase ketone bodies.

Path is due to type 2 bodies where body cant break down glucose and cant go through glycolysis to CAC. Produce tremendous amount of ketone bodies, Drops pH of blood which leads to death.