Question 1

Which organelle would you expect to be most abundant in a cell specialized for aerobic energy production, such as a cardiac muscle cell?

Accepted Answer

Mitochondria

Question 2

A liver cell from a person who consumes excessive alcohol is likely to have an increased proportion of which organelle, and why?

Accepted Answer

Smooth endoplasmic reticulum, to enhance detoxification

Question 3

Red blood cells lack most organelles, including the nucleus. What is the primary functional advantage of this adaptation?

Accepted Answer

It maximizes space for hemoglobin and oxygen transport

Question 4

Which of the following best explains why muscle cells have more mitochondria than skin cells?

Accepted Answer

Muscle cells require more ATP for contraction

Question 5

A protein destined for secretion from the cell is synthesized by ribosomes attached to which organelle?

Accepted Answer

Rough endoplasmic reticulum

Question 6

Which process involves the fusion of a vesicle with the plasma membrane, resulting in the release of its contents outside the cell?

Accepted Answer

Exocytosis

Question 7

What is the main function of the nuclear pore complex?

Accepted Answer

To regulate transport of molecules between the nucleus and cytoplasm

Question 8

Which signal is most likely to direct a newly synthesized protein to the lysosome?

Accepted Answer

A mannose-6-phosphate tag

Question 9

Why are tight junctions critical in the blood-brain barrier?

Accepted Answer

They prevent molecules from passing between cells, ensuring selective permeability

Question 10

Which type of cell junction allows for direct cytoplasmic exchange between adjacent animal cells?

Accepted Answer

Gap junctions

Question 11

A mutation in the gene encoding cadherin proteins would most directly affect which cellular structure?

Accepted Answer

Desmosomes

Question 12

Which of the following best describes the extracellular matrix (ECM) in animal cells?

Accepted Answer

A flexible network of proteins and carbohydrates that provides structural support and anchorage

Question 13

Which equation best represents the passive diffusion of nucleotides through the nuclear pore complex?

Accepted Answer

$$J = -D \frac{dC}{dx}$$

Question 14

If a cell increases its athletic activity, which organelle is most likely to increase in proportion over time?

Accepted Answer

Mitochondria

Question 15

Which of the following is a key difference between plant cell walls and animal extracellular matrix?

Accepted Answer

Plant cell walls are primarily composed of cellulose, while animal ECM contains more collagen

Question 16

Which process is exploited by viruses such as HIV and influenza to gain entry into host cells?

Accepted Answer

Endocytosis

Question 17

Which of the following best explains why the extracellular matrix is monitored via signals and why animal cells die if not properly anchored?

Accepted Answer

Anchorage is required for cell division and survival; loss of anchorage can trigger apoptosis

Question 18

Which of the following statements about ribosomes is correct?

Accepted Answer

Bound and free ribosomes are structurally and functionally identical; their location depends on the protein being synthesized

Question 19

Which cell junction is most likely to be defective in a patient with blistering skin diseases due to loss of cell adhesion?

Accepted Answer

Desmosomes

Question 20

Which of the following is true regarding the relationship between cell shape, organelle proportions, and cell function?

Accepted Answer

Organelle proportions and cell shape correlate with and help determine cell function

Cell Structure and Function: Organelle Proportions, Nuclear Transport, and Cell Surface Interactions

Study Guide - Practice Questions