Exam 4

Question 1

(Exam 4) The regulated step of triacylglycerol biosynthesis is:
-Acetyl-CoA synthetase
-Carnitine acyltransferase I
-Glycerol-3-phosphate acyltransferase
-Acyl Carrier protein
-ATP citrate lyase

Answer 1

-Glycerol-3-phosphate acyltransferase

Question 2

(Exam 4) Acetyl-CoA used to synthesize fatty acids:
-is generated in the cytoplasm via pyruvate dehydrogenase
-results from cholesterol metabolism
-is generated in the cytoplasm by ATP citrate lyase
-is synthesized in cytoplasm by acetyl-CoA synthase
-is synthesized in the mitochondria by acetyl-CoA synthetase

Answer 2

-is generated in the cytoplasm by ATP citrate lyase

Question 3

(Exam 4) __________ is the last common intermediate of triacylglycerol biosynthesis and all glycerophospholipid biosynthesis.
-Diacylglycerol
-Phosphatidic acid

Answer 3

-Phosphatidic acid

Question 4

(Exam 4) The rate-limiting step of fat mobilization (lipolysis) is:
-Hormone sensitive lipase
-Lipoprotein lipase
-Adipose triglyceride lipase
-Monoacylglycerol lipase
-Hepatic lipase

Answer 4

-Adipose triglyceride lipase

Question 5

(Exam 4) The regulated step of beta (β) oxidation is:
-Acetyl-CoA synthetase
-Carnitine acyltransferase I
-Glycerol-3-phosphate acyltransferase
-Acyl Carrier protein
-ATP citrate lyase

Answer 5

-Carnitine acyltransferase I

Question 6

(Exam 4)Ketolysis cannot occur in the liver as it lacks:
-HMG-CoA synthase
-3-oxoacid CoA transferase

Answer 6

-3-oxoacid CoA transferase

Question 7

(Exam 4) The final round of beta (β) oxidation will yield (assume odd number of saturated carbons):
-1 FADH2, 1 NADH, 2 acetyl-CoA
-1 NADH, 2 acetyl-CoA
-1 NADH, 1 acetyl-CoA, 1 propionyl-CoA
-1 FADH2, 1 NADH, 1 Acetyl-CoA, 1 propionyl-CoA
-1 FADH2, 1 NADH, 1 propionyl-CoA

Answer 7

-1 FADH2, 1 NADH, 1 Acetyl-CoA, 1 propionyl-CoA

Question 8

(Exam 4) Triacylglycerol (fat) synthesized in the liver is packaged into _________ so that it can be safely transported into the bloodstream.
-Chylomicron
-Very low density lipoprotein
-Intermediate density lipoprotein
-Low density lipoproteins
-High density lipoprotein

Answer 8

-Very low density lipoprotein

Question 9

(Exam 4) Lipoprotein lipases digest triacylglycerols (fat) in:
-very low density lipoproteins
-low density lipoproteins

Answer 9

-very low density lipoproteins

Question 10

(Exam 4) To digest triacylglycerol (fat), __________ requires colipase.
-pancreatic lipase
-lipoprotein lipase

Answer 10

-pancreatic lipase

Question 11

(Exam 4) Non-liver, non-steroidogenic tissues must acquire cholesterol from:
-chylomicron
-very low density lipoprotein
-intermediate density lipoprotein
-low density lipoprotein
-high density lipoprotein

Answer 11

-low density lipoprotein

Question 12

(Exam 4) All 27 carbon molecules found on cholesterol originate from:
-Acetyl-CoA
-Acyl-CoA
-Fatty acid
-Glucose
-Bile

Answer 12

-Acetyl-CoA

Question 13

(Exam 4) __________ are derived from arachidonic acid.
-Eicosanoids
-Lipid soluble vitamins

Answer 13

-Eicosanoids

Question 13

(Exam 4) The following molecule is:
-cholesterol
-a bile salt
-a steroid hormone
-vitamin D
-cholesteryl ester

Answer 13

-a steroid hormone

Question 13

(Exam 4) Cholesterol biosynthesis is activated in the presence of:
-Insulin
-Glucagon

Answer 13

-Insulin

Question 14

(Exam 4) In humans, glutamate is a common product of:
-transaminase (aminotransferase)
-glutamate dehydrogenase

Answer 14

-transaminase (aminotransferase)

Question 15

(Exam 4) Ubiquitination is required for protein degradation via:
-Glutamate dehydrogenase
-Cathepsins
-Digestive enzymes in stomach
-Digestive enzymes in small intestine
-Proteasome

Answer 15

-Proteasome

Question 16

(Exam 4) Which one of the following amino acids is not used for ammonia detoxification?
-Glutamate
-Glutamine
-Aspartate
-Alanine
-Methionine

Answer 16

-Methionine

Question 17

(Exam 4) Ammonia is used to synthesize ___________ in non-muscle tissue to safely transport ammonia to the liver.
-Glutamate
-Glutamine
-Alanine
-Pyruvate
-Carbamoyl phosphate

Answer 17

-Glutamine

Question 18

(Exam 4) The two NH3 groups used to synthesize urea enter the Urea Cycle via:
-carbamoyl phosphate and aspartate
-carbamoyl phosphate and glutamate
-carbamoyl phosphate and alanine
-carbamoyl phosphate and glutamine
-two carbamoyl phosphates

Answer 18

-carbamoyl phosphate and aspartate

Question 19

(Exam 4) In one carbon metabolism, methyl groups originate from:
-Glycine
-Methylated B12
-5-methyl-tetrahydrofolate
-Serine
-S-adenosylmethionine

Answer 19

-Serine

Question 20

(Exam 4) __________ synthesizes glutamine.
-Glutamine synthetase
-Glutaminase

Answer 20

-Glutamine synthetase

Question 21

(Exam 4) __________ is limited to only utilize glucose for energy production.
-The brain
-Erythrocytes

Answer 21

-Erythrocytes

Question 22

(Exam 4) Skeletal muscles can function under insufficient oxygen when using __________ as a fuel source.
-fatty acids
-amino acids
-ketone bodies
-glucose
-beer

Answer 22

-glucose

Question 23

(Exam 4) __________ can synthesize various fuels and redistribute them to other organs. -Skeletal muscles -Cardiac muscles -The liver -The brain -Erythrocytes

Answer 23

-The liver

Question 24

(Exam 4) Glycogenolysis in the liver is active during: -the fast state -starvation

Answer 24

-the fast state

Question 25

(Exam 4) During biochemical starvation: -there is insufficient glucose in the bloodstream for the organism to maintain long term function. -blood glucose remains relatively constant due to glucose export by the liver. -the liver utilizes amino acids as its major energy source -there is high blood glucose, but tissue that utilize a lot of glucose during the fed state do not respond. -adrenaline is synthesized to increase fuel supply to the cardiac and skeletal muscles.

Answer 25

-there is high blood glucose, but tissue that utilize a lot of glucose during the fed state do not respond.

Question 26

(Exam 4) Glucagon decreases __________ in the liver, while epinephrine increases __________ in the skeletal muscles. (Note: answer fills both blanks) -glycolysis -ketogenesis -glycogenolysis -glycogenesis -gluconeogenesis

Answer 26

-glycolysis

Question 27

(Exam 4) AMP-activated protein kinase (AMPk) is activated under: -Low energy charge -High energy charge -Energy efficiency -Glucagon -Insulin

Answer 27

-Low energy charge