Question 1

Which of the following best describes the process illustrated in the image, where multiple enzymes act sequentially on different substrates?

Accepted Answer

A metabolic pathway, where each enzyme catalyzes a specific step converting one substrate to another.

Question 2

If the final product (E) in the pathway shown acts as a feedback inhibitor, which enzyme would it most likely inhibit?

Accepted Answer

Enzyme 1, to prevent the pathway from starting when enough product is present.

Question 3

Which property of enzymes is illustrated by the fact that each substrate fits only one enzyme in the pathway?

Accepted Answer

Specificity, because each enzyme binds only to its unique substrate.

Question 4

If Enzyme 3 is inhibited by a noncompetitive inhibitor, what would happen to the pathway?

Accepted Answer

The pathway would slow down or stop at substrate C, since Enzyme 3 cannot convert C to D.

Question 5

Which of the following best describes the role of ATP in metabolic pathways like the one shown?

Accepted Answer

ATP provides energy for endergonic reactions, allowing substrates to be converted to products.

Question 6

If the pathway shown is regulated by negative feedback, which equation best represents the change in free energy ($$\Delta G) $$for the overall pathway if it is exergonic?

Accepted Answer

$$\Delta G \u003c 0$$

Question 7

Which of the following statements about the pathway is correct if the pathway is anabolic?

Accepted Answer

The pathway requires an input of energy, and the products have higher free energy than the reactants.

Question 8

If substrate B is converted to C by Enzyme 2, which type of reaction is most likely occurring?

Accepted Answer

A chemical reaction catalyzed by an enzyme, lowering the activation energy ($$E_A) $$required.

Question 9

If the pathway shown is part of cellular respiration, which step would most likely involve substrate-level phosphorylation?

Accepted Answer

A step where an enzyme directly transfers a phosphate group to ADP to form ATP.

Question 10

If the pathway is interrupted at Enzyme 2 due to a mutation, what is the most likely outcome?

Accepted Answer

Substrate B would accumulate, and downstream products C, D, and E would not be produced.

Question 11

Which of the following best explains why enzymes are not consumed in the pathway shown?

Accepted Answer

Enzymes catalyze reactions by lowering activation energy and are reusable after each reaction.

Question 12

If the pathway shown is regulated by allosteric inhibition, what would happen if an inhibitor binds to Enzyme 3 at a site other than the active site?

Accepted Answer

Enzyme 3 would change shape, reducing its activity and slowing the conversion of C to D.

Question 13

Which of the following is a correct statement about the transition state in enzyme-catalyzed reactions?

Accepted Answer

The transition state is a temporary state of maximum energy that enzymes help stabilize, lowering the activation energy.

Question 14

If the pathway shown is part of a metabolic pathway in a cell, what is the most likely effect of increasing temperature beyond the optimal range for the enzymes?

Accepted Answer

The enzymes may denature, losing their shape and function, and the pathway would slow down or stop.

BIO130T Exam 3 Review: Metabolism, Enzymes, Cellular Respiration, and Photosynthesis

Guida di studio - Domande di pratica

Study guide - Flashcard