Question

please answer and provide explanation to all

21. The following chart represents the order of electron flow through the electron transport chain. Select the step that is inhibited by cyanide (CN) or carbon monoxide (CO) NADH -> COQ -> Cyt b-> Cytel -> Cytc-> Cyt (a+a3) - > O2 a) NADH -> COQ b) CoQ - Cytb c) Cyt b-> Cytcl d) Cytel -> Cytc 22. The following chart represents the order of electron flow through the Electron Transport Chain. Select the step that is inhibited by the insecticide known as rotenone NADH -> COQ -> Cyt b->Cytel -> Cytc-> Cyt (ata3) -> 02 a) NADH -> COQ b) CoQ -> Cytb c) Cytb -> Cyt cl d) Cyt el -> Cytc 23. select the true statement about fatty acid metabolism. a) When cells require energy, epinephrine inhibits TG lipase. b) Enoyl CoA isomerase is required for the oxidation of saturated fatty acids c) 2,4-dienoyl-CoA reductase is required for the oxidation of polyunsaturated fatty acids d) succinyl-CoA is a product of oxidation of fatty acids with an even number of carbons 24. If a triacylglycerol, which consists of two-C14, and one- C17 fatty acid undergoes Stage 1 and Stage 2 oxidation, how many molecules of Acetyl-CoA, FADH2, and NADH will be formed? a) 22; 82; 41 b) 22, 83, 40 c)21, 82, 40 d) 21, 83, 41

Answer 1

21. Exact answer is cyt (a+a3)-->O2
Cyanide and CO2 inhibits cytochrome oxidase which has higher affinity to cynaide due to presence of sulphur compound in Cyt C oxidase.
Cyanide binds to Fe3+ ion in cytochrome a3.

22. NADH --> COQ

23. 2,4 dienoyl coA reductase required for oxidation of polyunsaturated fatty acids.

Epinephrine induces TG lipase foe fat breakdown.
Enoyl coA isomerase required for oxidation of unsaturated fatty acids

24. 21, 82, 40

Number of rounds in the Beta oxidation

(17/2) -1.5 = 8.5-1.5 = 7
Beta oxidation 7 cycle gives 7 Acetyl COA enter
7 FADH2, 7 NADH

Krebs cycle
22 NADH
8 FADH2

Myristic acid is a 14 carbon fatty acid.

Activation of the fatty acid to Acyl CoA = -2 ATP
Number of cycles in the Beta oxidation of mystric acid goes is (14/2) -1 = 6
6 FADH2
6 NADH
Beta oxidation 6 cycle gives 7 Acetyl COA enter

krebs cycle
21 NADH X 2 = 42
7 FADH2 X 2 = 7

Total
Acetyl cOA = 7 + 7 + 7 = 21