Question 1

Which of the following best describes the amphipathic nature of phospholipids in the cell membrane?

Accepted Answer

They have both hydrophilic heads and hydrophobic tails.

Question 2

A scientist uses FRAP (Fluorescence Recovery After Photobleaching) to study membrane fluidity. Which result would indicate a highly fluid membrane?

Accepted Answer

Rapid recovery of fluorescence in the bleached area.

Question 3

Which of the following statements about cholesterol in animal cell membranes is correct?

Accepted Answer

Cholesterol is amphipathic and modulates membrane fluidity.

Question 4

Which of the following best explains why type O blood is considered the universal donor?

Accepted Answer

Type O blood lacks A and B antigens on the surface of red blood cells.

Question 5

Which of the following is a function of the rough endoplasmic reticulum (RER)?

Accepted Answer

Synthesis of membrane-bound and secretory proteins.

Question 6

During vesicle budding, what is the primary role of coat proteins?

Accepted Answer

To help shape the budding vesicle and select cargo molecules.

Question 7

What is the function of the KDEL signal in protein sorting?

Accepted Answer

It retains soluble proteins in the endoplasmic reticulum or retrieves them from the Golgi.

Question 8

Which of the following best describes the difference between symport and antiport transporters?

Accepted Answer

Symporters move two molecules in the same direction; antiporters move them in opposite directions.

Question 9

A red blood cell is placed in a hypotonic solution. What will happen to the cell?

Accepted Answer

Water will enter the cell, causing it to swell and possibly burst.

Question 10

Which of the following best describes the function of v-SNARE proteins during vesicle fusion?

Accepted Answer

They interact with t-SNAREs on the target membrane to mediate vesicle docking and fusion.

Question 11

Which of the following statements about microtubules is correct?

Accepted Answer

Microtubules are polar structures composed of α- and β-tubulin heterodimers.

Question 12

Which motor protein moves toward the plus end of microtubules and is responsible for anterograde transport?

Accepted Answer

Kinesin

Question 13

What is the role of the γ-tubulin ring complex (γ-TuRC) in the centrosome?

Accepted Answer

It nucleates the assembly of new microtubules at the minus end.

Question 14

Which of the following best explains why the vesicle coat must be shed before vesicle fusion with the target membrane?

Accepted Answer

Uncoating exposes v-SNAREs, allowing them to interact with t-SNAREs on the target membrane.

Question 15

Which of the following is a key difference between simple diffusion and facilitated diffusion?

Accepted Answer

Facilitated diffusion requires membrane proteins, while simple diffusion does not.

Question 16

Which of the following best describes the process of cotranslational translocation?

Accepted Answer

A nascent polypeptide is inserted into the ER membrane as it is being synthesized by the ribosome.

Question 17

Which of the following statements about the mitotic spindle is correct?

Accepted Answer

It contains kinetochore, polar, and astral microtubules, each with distinct functions during mitosis.

Question 18

Which of the following best describes the function of lysosomes?

Accepted Answer

They degrade macromolecules and recycle cellular components.

Question 19

Which of the following is true regarding the polarity of microfilaments and microtubules?

Accepted Answer

Both microfilaments and microtubules are polar, with distinct plus and minus ends.

Question 20

Which of the following best describes the process of receptor-mediated endocytosis?

Accepted Answer

Specific molecules are internalized by binding to cell surface receptors, leading to vesicle formation.

Cell Membranes, Membrane Transport, Endomembrane System, and Cytoskeleton: Study Guide

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