Question

44.

1. The biosynthesis of ATP from ADP and a phosphate group donated by a metabolic intermediate is called

   	A.	oxidative phosphorylation
   	B.	photophosphorylation
   	C.	anaplerotic reaction
   	D.	substrate-level phosphorylation

46.

1. The following is incorrect regarding the statement "A small amount of ATP is made in glycolysis."

   	A.	Enzymes producing ATP from ADP + Pi, coupled with ΔGo < 0 reactions, are called kinases.
   	B.	Substrate-level phosphorylation depends on a ΔpH and a voltage gradient.
   	C.	ATP is formed by phosphoglycerate kinase and pyruvate kinase through substrate-level phosphorylation.
   	D.	A total investment of 2 ATPs renders a total of 4 ATPs with a net gain of 2 ATPs.

46.

1. The classical point of view is that, during mitochondrial respiration, three ATP molecules can be generated from one molecule of NADH + H⁺ and only two from FADH₂. When factoring in the cytosolic NADH + H⁺, the maximum number of molecules of ATP per glucose generated by the electron transport system is _____.

   	A.	2
   	B.	4
   	C.	36
   	D.	38 47

47.

1. The advantage to the cell of the gradual oxidation of glucose during cellular respiration compared with its combustion to CO₂ and H₂O in a single step is:

   	A.	energy can be extracted in usable amounts.
   	B.	more free energy is released for a given amount of glucose oxidized.
   	C.	no energy is lost as heat.
   	D.	more CO2 is produced for a given amount of glucose oxidized.

48.

1. What purpose does the phosphorylation of glucose to glucose 6-phosphate by the enzyme hexokinase serve as the first step in glycolysis?

   		It helps drive the uptake of glucose from outside the cell.
   		It generates a high-energy phosphate bond.
   		It converts ATP to a more useful form.
   		It enables the glucose 6-phosphate to be recognized by phosphofructokinase, the next enzyme in the glycolytic pathway.

49.

The products of the tricarboxylic acid cycle are:

	A.	carbon dioxide, GTP, NADH + H+, and FADH2
	B.	carbon dioxide, ADP, Acetyl-S-CoA and FAD
	C.	oxygen, ATP, NAD+, and FAD
	D.	oxygen, ATP, NADH, and FADH2

Answer 1

44) a) oxidative phosphorylation

Explanation- oxidative phosphorylation is a process occur in mitochondria and chloroplast for production of ATP with help of electrochemical gradient by transfer of electron from one carrier to another.

45) b) substrate level phosphorylation depends on delta pH and volatge gradient.

Explanation- susbtrate level phosphorylation do not depends on volatage gradient or delta pH. It depends on phosphorylation of ADP with help of energy transferred from high energy bonds of intermediate compounds.

46) c) 36 ATP

Explanation- Adding all the efforts of ATP including glycolysis, kreb cycle and ETS a total number of 36 ATPs are produced .

47)a) energy can be extracted in usuable amount

Explanation- a single step combustion will lead to loss of energy which could have been used efficiently for body processes. Slow oxidation give a control path for energy extraction as per requirements.

48) d) it enable glucose 6 phosphate to be recognised by enzyme phosphofructokinase next enzyme in series

Explanation- A metabolic pathway needs help of differnt enzymes which are specific to a single substrate. So, for process to continue susbtrate is required.

49) a) carbon dioxide, GTP, NADH+ H+ and FADH2

Explanation- TCA (tricarboxylic acid cycle) helps in metabolism of pyruvate produced by glycolysis to produce GTP , CO2 and energy bearing conpounds FADH2 and NADH+ H+