$$\text{Glucose} + O_2$ \rightarrow CO_2$ + H_2O + \text{ATP}$$

Question 1

Which of the following best describes the function of the nuclear localization signal (NLS) in eukaryotic cells?

Accepted Answer

It is a sequence of amino acids that enables proteins to be imported into the nucleus.

Question 2

A protein destined for secretion from a cell follows which pathway?

Accepted Answer

DNA → mRNA → ribosome → rough ER → vesicle → Golgi → plasma membrane

Question 3

Which cytoskeletal element is primarily responsible for muscle contraction and cell movement?

Accepted Answer

Actin filaments (microfilaments)

Question 4

During glycolysis, which enzyme catalyzes the rate-limiting step and is inhibited by high ATP levels?

Accepted Answer

Phosphofructokinase

Question 5

Which of the following equations correctly represents Gibbs free energy?

Accepted Answer

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

Question 6

A cell is exposed to a competitive inhibitor for an enzyme. Which of the following best describes the effect?

Accepted Answer

The inhibitor binds to the active site, preventing substrate binding.

Question 7

Which molecule acts as the final electron acceptor in the electron transport chain during cellular respiration?

Accepted Answer

Oxygen ($$O_2)$$

Question 8

In photosynthesis, which pigment is primarily responsible for absorbing blue and red light and reflecting green?

Accepted Answer

Chlorophyll a

Question 9

Which process allows cells to regenerate NAD⁺ in the absence of oxygen?

Accepted Answer

Fermentation

Question 10

A mutation causes the loss of the mannose-6-phosphate tag on a protein. Which cellular process would be most affected?

Accepted Answer

Targeting proteins to the lysosome

Question 11

Which of the following best explains why ATP is considered the main energy currency of the cell?

Accepted Answer

ATP releases energy by breaking its phosphate bonds, which can be used to drive endergonic reactions.

Question 12

Which cytoskeletal motor protein moves vesicles toward the plus end of microtubules?

Accepted Answer

Kinesin

Question 13

Which of the following is a correct net equation for cellular respiration?

Accepted Answer

$$	ext{Glucose} + O_2$ ightarrow CO_2$ + H_2O + 	ext{ATP}$$

Question 14

Which enzyme is responsible for catalyzing the fixation of carbon dioxide in the Calvin cycle?

Accepted Answer

Rubisco

Question 15

A cell is placed in an environment with a high concentration of ATP. Which step of glycolysis is most likely to be inhibited?

Accepted Answer

Step 3: Fructose-6-phosphate phosphorylation by phosphofructokinase

Question 16

Which of the following statements about the electron transport chain (ETC) is correct?

Accepted Answer

Electrons are transferred through a series of complexes, creating a proton gradient across the inner mitochondrial membrane.

Question 17

Which of the following best describes the role of the signal recognition particle (SRP) during protein synthesis?

Accepted Answer

SRP binds to the ER signal sequence, pauses translation, and directs the ribosome to the rough ER.

Question 18

Which of the following is a major function of carotenoids in plant cells?

Accepted Answer

They protect chlorophyll from damage by free radicals and transfer energy to chlorophyll.

Question 19

Which of the following best explains why the Calvin cycle keeps the concentration of CO₂ low inside the leaf?

Accepted Answer

It drives diffusion of CO₂ into the leaf by maintaining a concentration gradient.

Question 20

Which of the following statements about enzyme catalysis is correct?

Accepted Answer

Enzymes lower the activation energy by stabilizing the transition state.

Cell Structure, Energy, and Metabolism: Study Notes for College Biology

Study Guide - Practice Questions