Question 1

Which statement best describes the first law of thermodynamics as it applies to biological systems?

Accepted Answer

Energy can be transferred or transformed, but it cannot be created or destroyed.

Question 2

A cell synthesizes a protein from amino acids. Which type of metabolic pathway is this an example of?

Accepted Answer

Anabolic pathway

Question 3

During cellular respiration, glucose is broken down in the presence of oxygen. What type of pathway and reaction is this?

Accepted Answer

Catabolic pathway and exergonic reaction

Question 4

Which of the following best illustrates the second law of thermodynamics in living systems?

Accepted Answer

Energy transfer or transformation increases the entropy (disorder) of the universe.

Question 5

A diver climbs up a platform, converting the kinetic energy of muscle movement into potential energy. When the diver jumps, what energy transformation occurs?

Accepted Answer

Potential energy is converted into kinetic energy.

Question 6

Which equation correctly represents the change in free energy ($$\Delta G) $$for a chemical reaction?

Accepted Answer

$$\Delta G = \Delta H - T\Delta S$$

Question 7

Which of the following is true about exergonic reactions?

Accepted Answer

They proceed with a net release of free energy ($$\Delta G \u003c 0).$$

Question 8

What is the role of enzymes in metabolic reactions?

Accepted Answer

Enzymes speed up reactions by lowering the activation energy barrier.

Question 9

Which of the following statements about enzyme specificity is correct?

Accepted Answer

Each enzyme catalyzes only one specific reaction due to its unique active site.

Question 10

A competitive inhibitor affects enzyme activity by:

Accepted Answer

Competing with the substrate for binding at the active site.

Question 11

Which of the following best describes feedback inhibition in metabolic pathways?

Accepted Answer

The end product of a pathway inhibits an earlier enzyme, preventing overproduction.

Question 12

ATP hydrolysis releases energy. Which chemical equation best represents this process?

Accepted Answer

$$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} ightarrow \mathrm{ADP} + \mathrm{P}_i + 	ext{energy}$$

Question 13

Which statement about the effect of temperature on enzyme activity is correct?

Accepted Answer

Each enzyme has an optimal temperature at which it functions most efficiently.

Question 14

In a metabolic pathway, the product of one reaction often serves as the substrate for the next. What is the advantage of this organization?

Accepted Answer

It prevents the accumulation of intermediates and keeps the pathway moving forward.

Question 15

Which of the following is a real-life example of energy coupling in cells?

Accepted Answer

Using the energy released from ATP hydrolysis to drive the active transport of ions across a membrane.

Question 16

Which type of enzyme regulation involves a molecule binding to a site other than the active site, causing a change in enzyme activity?

Accepted Answer

Allosteric regulation

Question 17

Which of the following is NOT a function of ATP in cellular work?

Accepted Answer

Serving as a long-term energy storage molecule.

Question 18

A cell is considered an open system because:

Accepted Answer

It constantly exchanges energy and matter with its environment.

Question 19

Which of the following statements about cofactors is correct?

Accepted Answer

Cofactors are non-protein helpers that assist enzymes in catalysis.

Chapter 8: An Introduction to Metabolism (General Biology Study Notes)

Guida di studio - Domande di pratica

Study guide - Flashcard