Question 1

Which of the following best explains why muscle cells in athletes have a higher proportion of mitochondria compared to liver cells in non-athletes?

Accepted Answer

Muscle cells require more energy for contraction, so they have more mitochondria to produce ATP.

Question 2

A protein destined for the nucleus must have which of the following features to be imported?

Accepted Answer

A nuclear localization signal (NLS)

Question 3

Which process increases the size of a cell by adding new membrane material?

Accepted Answer

Exocytosis

Question 4

What is the primary function of the cytoskeleton in eukaryotic cells?

Accepted Answer

Provide structural support, maintain cell shape, and organize internal contents

Question 5

Which of the following statements about nuclear transport is correct?

Accepted Answer

Large molecules require specific signals to be imported into the nucleus via nuclear pore complexes.

Question 6

A scientist adds a nuclear localization signal (NLS) to a cytoplasmic protein. What is the most likely outcome?

Accepted Answer

The protein will be imported into the nucleus.

Question 7

Which of the following is TRUE regarding the extracellular matrix (ECM) in animal cells?

Accepted Answer

It is more bendable than plant cell walls and contains more protein and less carbohydrate.

Question 8

Which cell junction is most likely to be found in the epithelial lining of the stomach, preventing the passage of solutes between cells?

Accepted Answer

Tight junctions

Question 9

Desmosomes are important for cell adhesion. Which protein is specifically involved in their function?

Accepted Answer

Cadherins

Question 10

Which of the following best describes the difference between 'free' and 'bound' ribosomes?

Accepted Answer

They are structurally and functionally identical; the only difference is the type of protein they are making at a given time.

Question 11

A mutation prevents the formation of tight junctions in epithelial cells. What is the most likely physiological consequence?

Accepted Answer

Increased leakage of solutes between cells

Question 12

Which of the following is a function of the Golgi apparatus in protein sorting?

Accepted Answer

Adding localization signals such as mannose-6-phosphate to proteins destined for lysosomes

Question 13

During endocytosis, what happens to the size of the cell?

Accepted Answer

It decreases because plasma membrane is internalized.

Question 14

Which of the following statements about fiber composites in eukaryotic cells is correct?

Accepted Answer

Plant cell walls contain cellulose fibers that resist tension and pectin that resists compression.

Question 15

Which of the following best describes the role of motor proteins in vesicle transport?

Accepted Answer

They use ATP to 'walk' along microtubules, moving vesicles within the cell.

Question 16

A virus exploits endocytosis to enter a cell. Which step is most critical for the virus to gain entry?

Accepted Answer

Binding to a specific receptor on the cell surface

Question 17

Which of the following equations correctly represents the energy usage by motor proteins during vesicle transport?

Accepted Answer

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

Question 18

Which structure allows direct communication between adjacent plant cells?

Accepted Answer

Plasmodesmata

Question 19

Intercalated discs in heart muscle are an example of which type of cell connection?

Accepted Answer

Desmosomes

Question 20

Which of the following best explains why animal cells have a wider variety of cell connections than plant cells?

Accepted Answer

Animal cells are held together by ECM, cell-cell adhesions, and have more types of junctions.

Cell Structure, Function, and Interactions: Organelle Proportions, Endomembrane System, Cytoskeleton, and Cell Connections

Study Guide - Practice Questions