Lipids

Question 1

L1: ______ is the enzyme in the rate-limiting step of cholesterol synthesis.

Answer 1

HMG CoA reductase

Question 2

L1: Acetyl CoA is transported from the mitochondrion to the cytosol in fatty acid synthesis by conversion to _______.

Answer 2

Citrate

Question 3

L1: At mild to moderate exercise, _____ provides the primary source of energy for ATP synthesis.

Answer 3

Fat

Question 4

L1: During vigorous exercise, _____ provides the primary source of energy for ATP synthesis.

Answer 4

Carbohydrates

Question 5

L1: Geranyl pyrophosphate, farnesyl pyrophosphate, and squalene are intermediates in synthesis of _____.

Answer 5

Cholesterol

Question 6

L1: In order to be transported into the mitochondria for beta oxidation, fatty acyl CoA is conjugated to ______.

Answer 6

Carnitine

Question 7

L1: The rate limiting enzyme in fatty acid breakdown is _______.

Answer 7

Carnitine Palmitoyl Transferase 1 (CPT1)

Question 8

L1: What % of caloric intake is accounted for by fat?

Answer 8

25-35%

Question 9

L1: What enzyme activates hormone-sensitive lipase?

Answer 9

Protein Kinase A

Question 10

L1: What is a required coenzyme for acetyl CoA carboxylase?

Answer 10

Biotin

Question 11

L1: What is the rate limiting enzyme in cholesterol synthesis?

Answer 11

HMG CoA reductase

Question 12

L1: What type of fat? Fish and seafood

Answer 12

Omega-3 fat

Question 13

L1: What type of fat? Margarine, processed foods

Answer 13

Trans fats

Question 14

L1: Which lipid? Important in signal transduction, reservoir for arachidonic acid

Answer 14

Phosphatidylinositol

Question 15

L1: Which lipid? Most abundant phospholipid in the body, important in lung surfactant, present in bile

Answer 15

Phosphatidylcholine

Question 16

L1: Which lipoprotein? 10:1 triglyceride:cholesterol ratio, very large

Answer 16

Chylomicrons

Question 17

L1: Which lipoprotein? Reservoir of phospholipids

Answer 17

HDL

Question 18

L1: Which lipoprotein? Very atherogenic, more cholesterol than triglycerides

Answer 18

LDL

Question 19

L1: Which tissue contains glycerol kinase, which can convert glycerol directly to glycerol-phosphate?

Answer 19

Liver

Question 20

L2: _____ catalyzes exchange of cholesterol esters and triglycerides between VLDL and HDL.

Answer 20

Cholesterol Ester Binding Protein (CETP)

Question 21

L2: _____ is produced in the rate limiting step of ketone body synthesis.

Answer 21

HMG CoA

Question 22

L2: ______ are the ketones produced in ketogenesis.

Answer 22

3-hydroxybutyrate, Acetone

Question 23

L2: ______ catalyzes transfer of a fatty acid to cholesterol to trap it in HDL.

Answer 23

Lecithin Cholesterol Acyltransferase (LCAT)

Question 24

L2: ______ is produced in the rate-limiting step of cholesterol synthesis.

Answer 24

Mevalonate

Question 25

L2: Beta oxidation in the mitochondira involves __ steps and produces _______.

Answer 25

4; NADH, FADH2, acetyl-CoA

Question 26

L2: Fatty acid addition to glycerol is catalyzed by _______.

Answer 26

Acyltransferase

Question 27

L2: Fatty acids are desaturated by ________ in the ER.

Answer 27

Mixed Function Oxidases

Question 28

L2: How does insulin increase the action of acetyl CoA carboxylase?

Answer 28

Activation of phosphoprotein phosphatase to dephosphorylate acetyl CoA carboxylase to its active form

Question 29

L2: In negative energy states, triglycerides are broken down by ________.

Answer 29

Hormone-sensitive lipase

Question 30

L2: Malonyl CoA is converted to _______ by ______ in fatty acid synthesis.

Answer 30

Palmitic acid; fatty acid synthase

Question 31

L2: Name two fatty acids that must be obtained from the diet.

Answer 31

Linoleic acid, linolenic acid

Question 32

L2: Polymerization of Acetyl CoA carboxylase ______ its function.

Answer 32

increases

Question 33

L2: The initial substrate for ketogenesis is _______.

Answer 33

Acetyl CoA

Question 34

L2: What enzyme is rate-limiting in fatty acid synthesis?

Answer 34

Acetyl CoA Carboxylase

Question 35

L2: What facilitates transport of cholesterol from tissues to HDL

Answer 35

ABC-A1 binding cassette

Question 36

L2: What is a key inhibitor of CPT1?

Answer 36

Malonyl CoA

Question 37

L2: What is produced in the rate-limiting step in fatty acid synthesis?

Answer 37

Malonyl CoA

Question 38

L2: What is the ligand for the LDL receptor?

Answer 38

apoprotein B100

Question 39

L2: What is the ligand for the remnant particle receptor?

Answer 39

apoprotein E

Question 40

L2: What is the rate limiting enzyme in beta oxidation?

Answer 40

Carnitine Palmitoyl Transferase 1 (CPT1)

Question 41

L2: What is the rate limiting enzyme in ketogenesis?

Answer 41

HMG CoA synthase

Question 42

L2: What type of fat? Manteca, red meat fat, lard

Answer 42

Saturated

Question 43

L2: What type of fat? Olive oil and canola oil

Answer 43

Monounsaturated fat

Question 44

L2: What type of fat? Vegetable and corn oils

Answer 44

Omega-6 fat

Question 45

L2: When a fatty acid has an odd number of carbons, the final three carbon molecule, ______, is converted to _______.

Answer 45

Proprionyl CoA, succinyl CoA

Question 46

L2: Which apoproteins are present on newly synthesized chylomicrons? Which are acquired in circulation?

Answer 46

B48; C2, E

Question 47

L2: Which apoproteins are present on newly synthesized HDL? Which are acquired in circulation?

Answer 47

A1, C2, E; none

Question 48

L2: Which apoproteins are present on newly VLDL/LDL? Which are acquired in circulation?

Answer 48

B100; C2, E

Question 49

L2: Which fatty acid synthesis intermediate activates Acetyl CoA carboxylase?

Answer 49

Citrate

Question 50

L2: Which fatty acid synthesis intermediate inhbits Acetyl CoA carboxylase?

Answer 50

Malonyl CoA

Question 51

L2: Which glycolysis intermediate can be converted to glycerol for fatty acid synthesis? What tissues does this occur in?

Answer 51

Dihydroxyacetone-Phosphate; Liver and adipose tissue

Question 52

L2: Which lipoprotein? Atherogenic, 1:1 triglyceride:cholesterol ratio

Answer 52

Remnant Particles

Question 53

L3: What additional enzymes may be required for breakdown of unsaturated fatty acids?

Answer 53

3,2-enoyl CoA isomerase, NADPH-dependent reductase