$ \text{Net movement} = D \times (C_1 - C_2) $

$ \text{ATP} + \text{H}_2\text{O} \rightarrow \text{ADP} + \text{P}_i + \text{energy} $

Question 1

Which of the following best describes the plasma membrane's property of selective permeability?

Accepted Answer

It allows certain molecules to pass while restricting others based on size, charge, and solubility.

Question 2

A red blood cell is placed in a hypertonic solution. What is the most likely outcome?

Accepted Answer

The cell will shrink (crenate) as water moves out of the cell.

Question 3

Which process requires cellular energy (ATP) to move substances against their concentration gradient?

Accepted Answer

Active transport

Question 4

Which equation best represents the movement of molecules during diffusion?

Accepted Answer

$ 	ext{Net movement} = D 	imes (C_1 - C_2) $

Question 5

Which of the following substances can diffuse directly through the lipid bilayer of the plasma membrane?

Accepted Answer

Oxygen

Question 6

Facilitated diffusion of glucose across the plasma membrane is limited by which factor?

Accepted Answer

The number of carrier proteins available

Question 7

Which type of membrane transport involves the movement of water through aquaporins?

Accepted Answer

Osmosis

Question 8

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

Accepted Answer

It will gain water and swell, possibly bursting (lysis).

Question 9

Which of the following is true about carrier-mediated facilitated diffusion?

Accepted Answer

It is specific for certain molecules and moves them down their concentration gradient.

Question 10

The sodium-potassium pump is an example of which type of transport?

Accepted Answer

Primary active transport

Question 11

Which equation correctly represents the hydrolysis of ATP during active transport?

Accepted Answer

$ 	ext{ATP} + 	ext{H}_2	ext{O} ightarrow 	ext{ADP} + 	ext{P}_i + 	ext{energy} $

Question 12

Which process is responsible for the uptake of large particles, such as bacteria, by white blood cells?

Accepted Answer

Phagocytosis

Question 13

Which of the following best describes secondary active transport?

Accepted Answer

It relies on ionic gradients created by primary active transport to move substances.

Question 14

Which type of transport is used to secrete hormones, neurotransmitters, and mucus from cells?

Accepted Answer

Exocytosis

Question 15

A patient receives an intravenous solution that is isotonic to their blood cells. What is the expected effect on the cells?

Accepted Answer

Cells will remain stable as water moves freely in and out.

Question 16

Which of the following is a key difference between channel-mediated and carrier-mediated facilitated diffusion?

Accepted Answer

Carrier-mediated diffusion involves a shape change in the protein, while channel-mediated does not.

Question 17

Which equation best represents osmotic pressure ($ \Pi $) in terms of solute concentration?

Accepted Answer

$ \Pi = iMRT $

Question 18

Which process is most likely to be hijacked by pathogens to enter a cell?

Accepted Answer

Receptor-mediated endocytosis

Question 19

Which of the following statements about cotransporters is correct?

Accepted Answer

They move two different substances in the same direction across the membrane.

Question 20

A cell is actively transporting sodium ions out and potassium ions in. Which equation best represents this process?

Accepted Answer

$ 3	ext{Na}^+_{	ext{in}} + 2	ext{K}^+_{	ext{out}} + 	ext{ATP} ightarrow 3	ext{Na}^+_{	ext{out}} + 2	ext{K}^+_{	ext{in}} + 	ext{ADP} + 	ext{P}_i $

Cell Physiology: Plasma Membrane Transport

Study Guide - Practice Questions