Question 1

Which of the following best describes the process of diffusion across a cell membrane?

Accepted Answer

Movement of particles down their concentration gradient until equilibrium is reached.

Question 2

A red blood cell is placed in a solution with an osmolarity of 400 mOsm/L. What will happen to the cell?

Accepted Answer

It will shrink due to net water efflux.

Question 3

Which equation correctly calculates the osmolarity of a 2 mM solution of CaCl$$_2$$?

Accepted Answer

$$2	imes3=6$$ mOsm/L

Question 4

Which property is NOT characteristic of protein-mediated transport across plasma membranes?

Accepted Answer

Unlimited transport rate regardless of solute concentration

Question 5

A patient receives an intravenous solution that is hypotonic compared to their blood plasma. What is the most likely effect on their red blood cells?

Accepted Answer

Cells will swell and may burst due to water influx.

Question 6

Which of the following is TRUE regarding the sodium-potassium pump (Na$$^+-K$^+$$ ATPase)?

Accepted Answer

It moves 3 Na$$^+$$ out of the cell and 2 K$$^+$$ into the cell, consuming ATP.

Question 7

Which of the following best explains why facilitated diffusion exhibits saturable kinetics?

Accepted Answer

Carrier proteins can only transport one solute at a time and must undergo a conformational change.

Question 8

A cell is placed in a solution containing 120 mM NaCl, 5 mM KCl, 4 mM CaCl$$_2$$, 10 mM glucose, and 9 mM Na$$_2SO$_4. $$What is the total osmolarity of the solution?

Accepted Answer

$$240+10+12+10+27=299$$ mOsm/L

Question 9

Which of the following statements about secondary active transport is correct?

Accepted Answer

It relies on the gradient established by primary active transport, such as the Na$$^+$$ gradient.

Question 10

Which of the following is an example of bulk flow rather than diffusion?

Accepted Answer

Blood being pumped through arteries by the heart

Question 11

Which of the following mechanisms is responsible for the uptake of large particles, such as bacteria, into a cell?

Accepted Answer

Phagocytosis

Question 12

What is the main difference between facilitated diffusion and active transport?

Accepted Answer

Facilitated diffusion moves solutes down their concentration gradient, while active transport moves them against the gradient using energy.

Question 13

Which of the following best describes the effect of a hypertonic solution on an animal cell?

Accepted Answer

Net movement of water out of the cell; cell shrinks.

Question 14

Which of the following is TRUE about aquaporins?

Accepted Answer

They are water channels that facilitate osmosis without direct use of ATP.

Question 15

A cell uses a symporter to transport glucose and Na$$^+$$ into the cell. Which type of transport is this?

Accepted Answer

Secondary active transport

Question 16

Which of the following statements about the resting membrane potential is correct?

Accepted Answer

It is maintained by the Na$$^+-K$^+$$ ATPase, which is electrogenic.

Question 17

Which process involves the ejection of materials from the cell via vesicles?

Accepted Answer

Exocytosis

Question 18

Which of the following would most likely compete for the same carrier protein during facilitated diffusion?

Accepted Answer

Glucose and galactose

Question 19

Which of the following is NOT a property of channels involved in facilitated diffusion?

Accepted Answer

They require ATP to function.

Question 20

A cell in a solution with 250 mOsm/L extracellular osmolarity will experience which of the following?

Accepted Answer

Net movement of water into the cell, causing it to swell.

Membrane Transport: Mechanisms and Physiological Significance

Study Guide - Practice Questions

Study Guide - Flashcards