Question 1

Which of the following best explains why muscle cells contain a higher proportion of mitochondria compared to red blood cells?

Accepted Answer

Muscle cells require more energy for contraction, so they need more mitochondria for ATP production.

Question 2

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

Accepted Answer

Smooth endoplasmic reticulum, because it is involved in detoxification of harmful substances.

Question 3

Which of the following best describes the relationship between organelle proportions and cell function?

Accepted Answer

Organelle proportions, along with cell size and shape, correlate with the cell's function.

Question 4

A scientist observes a cell with a large number of rough endoplasmic reticulum and prominent Golgi apparatus. Which primary function is this cell most likely specialized for?

Accepted Answer

Synthesis and secretion of proteins.

Question 5

Which of the following is a correct statement about the nuclear envelope?

Accepted Answer

It is a double membrane that surrounds the nucleus and regulates the movement of molecules in and out.

Question 6

Which HIV protein is most likely to have a nuclear localization signal (NLS) and why?

Accepted Answer

Integrase, because it must enter the nucleus to integrate viral DNA into the host genome.

Question 7

During protein synthesis, what determines whether a ribosome will become bound to the endoplasmic reticulum (ER)?

Accepted Answer

The presence of a signal sequence on the growing polypeptide chain.

Question 8

Which of the following best describes the process of exocytosis?

Accepted Answer

A vesicle merges with the plasma membrane, releasing its contents outside the cell.

Question 9

A cell in the intestinal lining is specialized for transporting small molecules and ions across the plasma membrane. Which structure is most critical for this function?

Accepted Answer

Endoplasmic reticulum, because it produces membrane proteins such as channels and transporters.

Question 10

Researchers attempted to reconstitute vesicle transport in vitro by assembling microtubules, vesicles, and ATP, but observed no movement. What essential component did they likely forget to include?

Accepted Answer

Motor proteins, which use ATP to move vesicles along microtubules.

Question 11

Hereditary spherocytosis is a disorder associated with a defective cytoskeletal protein in red blood cells (RBCs). What is a likely consequence of this defect?

Accepted Answer

Insufficient supply of oxygen-transporting proteins in the RBCs due to abnormal cell shape.

Question 12

Which of the following statements about the extracellular matrix (ECM) in animal cells is correct?

Accepted Answer

The ECM is more flexible and contains more protein (especially collagen) than a plant cell wall.

Question 13

Which type of cell-to-cell connection is most important in forming a watertight seal between adjacent cells, such as those in the blood-brain barrier?

Accepted Answer

Tight junctions

Question 14

In an experiment, cells from two different sponge species are mixed and reassemble into separate species. What does this suggest about the molecules responsible for cell-cell adhesion?

Accepted Answer

The molecules responsible for cell-cell adhesion differed between the two species.

Question 15

Which of the following best describes the function of gap junctions in animal cells?

Accepted Answer

They connect the cytoplasm of adjacent cells, allowing for coordination of cellular activities.

Question 16

Which of the following is a similarity between plant cell walls and the extracellular matrix (ECM) of animal cells?

Accepted Answer

Proteins that are part of the cell wall/ECM are made by ribosomes attached to the rough ER and then secreted.

Question 17

Which equation best represents the energy requirement for active transport of ions across a membrane?

Accepted Answer

$$ \Delta G = \Delta G^0$ + RT \ln \left( \frac{[C]_2}{[C]_1} \right) + zF\Delta \Psi $$

Question 18

A mutation causes a cell to lack functional desmosomes. Which of the following would most likely result?

Accepted Answer

Cells would be less securely attached to each other, making tissues more prone to mechanical stress.

Organelle Proportions and Cell Structure-Function Relationships

Study Guide - Practice Questions

Study Guide - Flashcards