Methylmalonyl CoA mutase contains vitamin B12 as its coenzyme. What is the substrate for this enzyme?
succinyl CoA
trans-Δ3-enoyl CoA
D-glyceraldehyde 3-phosphate
propionyl CoA
trans-Δ2-enoyl CoA
2. How many molecules of acetyl CoA are involved in a single round of ketogenesis?
4
3
2
0
1
3. Which compound does β oxidation begin from?
acyl carnitine
CoA
trans-Δ2-enoyl CoA
acetyl CoA
acyl CoA
4. How does activated fatty acid move to the mitochondrial matrix?
The activated fatty acid moves across the outer mitochondrial membrane through a porin channel, and shuttles across the inner mitochondrial membrane by a translocase.
The activated fatty acid moves across the outer mitochondrial membrane through a porin channel. Acetyl carnitine shuttles across the inner mitochondrial membrane by a translocase.
The activated fatty acid moves across the outer mitochondrial membrane by passive diffusion. Acetyl carnitine moves across the inner mitochondrial membrane by a translocase.
D-glyceraldehyde 3-phosphate moves across the outer mitochondrial membrane through a porin channel, and shuttles across the inner mitochondrial membrane by a translocase.
Acetyl carnitine moves across the outer mitochondrial membrane through a porin channel, and shuttles across the inner mitochondrial membrane by a translocase.
5. Every biochemistry student knows that most naturally occurring unsaturated fatty acids are cis fatty acids. Why, then, do so many fat-containing foods come with the notation "Contains no trans fats"?
Oils that contain an odd number of carbon atoms are particularly susceptible to oxidation to trans fats. Thus, no odd-numbered carbon fatty acids are used in these foods.
Olive oils, normally healthy oils, are converted to trans fat when cooked at high temperatures. Thus, olive oils are used only at low temperatures.
Vegetable oils are often hydrogenated to form trans unsaturated fatty acids to preserve shelf life.
Vegetable oils contain polyunsaturated fatty acids prone to oxidation, which then converts them to trans fats.
6. The increase in acetyl CoA during starvation inhibits the enzyme:
pyruvate dehydrogenase.
hormone-sensitive lipase.
glucagon.
cobalamin.
acyl CoA dehydrogenase.
7. Which compound is an intermediate in ketogenesis?
D-methylmalonyl CoA
3-hydroxy-3-methyl-glutaryl CoA
D-3-hydroxybutyrate
L-methylmalonyl CoA
acetone
8. During triacylglycerol hydrolysis, hormone-sensitive lipase catalyzes the release of:
glycerol and a single free fatty acid.
diacylglycerol and a single free fatty acid.
monoacylglycerol and two free fatty acids.
glycerol and three free fatty acids.
monoacylglycerol and a single free fatty acid.