Question 1

Which of the following best describes the structure of the plasma membrane?

Accepted Answer

A double layer of phospholipids with embedded proteins

Question 2

Which process requires ATP to move substances across the plasma membrane?

Accepted Answer

Primary active transport

Question 3

The Na+/K+-ATPase pump moves sodium and potassium ions in which direction and ratio?

Accepted Answer

3 Na+ out, 2 K+ in

Question 4

Which equation best represents the electrochemical gradient established by the Na+/K+-ATPase pump?

Accepted Answer

$E = RT \over F \cdot \ln \left( \frac{[K^+]_{in} \cdot [Na^+]_{out}}{[K^+]_{out} \cdot [Na^+]_{in}} \right)$

Question 5

Which type of membrane transport is described as 'downhill' movement of molecules along their concentration gradient without energy input?

Accepted Answer

Facilitated diffusion

Question 6

A patient is diagnosed with a genetic defect in the Na+/K+-ATPase pump. Which of the following cellular consequences is most likely?

Accepted Answer

Increased intracellular Na+ and decreased membrane potential

Question 7

Which of the following is an example of secondary active transport?

Accepted Answer

Glucose transport coupled with Na+ influx

Question 8

During receptor-mediated endocytosis, which structure is responsible for concentrating and internalizing specific ligands?

Accepted Answer

Clathrin-coated pits

Question 9

Which of the following best describes the difference between symport and antiport in secondary active transport?

Accepted Answer

Symport moves two solutes in the same direction; antiport moves them in opposite directions

Question 10

Which process allows white blood cells to engulf bacteria?

Accepted Answer

Phagocytosis

Question 11

A cell is placed in a hypotonic solution. What will happen to the cell due to osmosis?

Accepted Answer

The cell will swell as water enters

Question 12

Which formula best describes the rate of facilitated diffusion through a membrane transporter?

Accepted Answer

$J = V_{max} \cdot \frac{[S]}{K_m + [S]}$

Question 13

Which of the following is NOT a function of membrane proteins?

Accepted Answer

Forming the phospholipid bilayer

Question 14

Which of the following statements about the Na+/K+-ATPase pump is correct?

Accepted Answer

It hydrolyzes ATP to move ions against their concentration gradients

Question 15

Which type of endocytosis is used by cells to sample the extracellular environment by bringing in fluid and solute particles?

Accepted Answer

Pinocytosis

Question 16

A drug inhibits clathrin-mediated endocytosis. Which cellular process would be most directly affected?

Accepted Answer

Uptake of low-density lipoproteins (LDL)

Question 17

Which of the following best explains why the Na+/K+-ATPase pump is considered an electrogenic pump?

Accepted Answer

It creates a net movement of positive charge out of the cell

Question 18

Which of the following is a real-world example of secondary active transport in human physiology?

Accepted Answer

Glucose absorption in the small intestine via SGLT1

Question 19

Which of the following is a key feature of receptor-mediated endocytosis compared to other forms of endocytosis?

Accepted Answer

It concentrates specific ligands using protein-coated pits

Question 20

Which of the following best describes the role of G protein-coupled receptors (GPCRs) in cell signaling?

Accepted Answer

They activate intracellular signaling cascades upon ligand binding

Membrane Transport: Cellular Physiology in Anatomy & Physiology

Study Guide - Practice Questions