$$\text{Water moves from an area of high water potential to low water potential}$$

Question 1

Which of the following statements best describes simple diffusion across the plasma membrane?

Accepted Answer

It is the movement of small molecules from an area of high concentration to low concentration without energy input.

Question 2

Facilitated diffusion differs from simple diffusion in that:

Accepted Answer

Facilitated diffusion uses channel or carrier proteins to move specific molecules across the membrane.

Question 3

A red blood cell placed in a hypotonic solution will:

Accepted Answer

Become lysed as water enters the cell by osmosis.

Question 4

Which equation best represents the net movement of water during osmosis?

Accepted Answer

$$	ext{Water moves from an area of high water potential to low water potential}$$

Question 5

Which of the following is NOT a characteristic of passive transport?

Accepted Answer

It moves substances against their concentration gradient.

Question 6

A plant cell in a hypertonic solution will most likely:

Accepted Answer

Become plasmolyzed as water leaves the cell.

Question 7

Which process involves the plasma membrane pinching inward to take in large molecules?

Accepted Answer

Endocytosis

Question 8

During facilitated diffusion, which type of protein alternates between two shapes to move a solute across the membrane?

Accepted Answer

Carrier protein

Question 9

Which of the following best explains why animal cells fare best in an isotonic environment?

Accepted Answer

There is no net movement of water into or out of the cell, preventing lysis or shrinkage.

Question 10

A cell is placed in an isotonic solution. Which of the following will occur?

Accepted Answer

There will be no net movement of water across the membrane.

Question 11

Which of the following is a real-life example of facilitated diffusion?

Accepted Answer

Glucose entering a muscle cell through a GLUT transporter.

Question 12

Which process is responsible for the secretion of large molecules such as hormones from a cell?

Accepted Answer

Exocytosis

Question 13

If a cell's plasma membrane is damaged and cannot regulate transport, which of the following is most likely to occur?

Accepted Answer

The cell will lose control over its internal environment, possibly leading to cell death.

Question 14

Which of the following best describes the role of receptor proteins in cell signaling?

Accepted Answer

They bind signaling molecules, triggering cellular changes.

Question 15

Which of the following equations describes the rate of diffusion according to Fick's law?

Accepted Answer

$$J = -D \frac{dC}{dx}$$

Question 16

A plant cell is placed in a hypotonic solution. What is the expected outcome?

Accepted Answer

The cell will become turgid as water enters.

Question 17

Which of the following is true about channel proteins in facilitated diffusion?

Accepted Answer

They form open pores that allow specific molecules to pass through the membrane.

Question 18

Which scenario best illustrates the concept of bulk transport?

Accepted Answer

A white blood cell engulfing a bacterium by endocytosis.

Question 19

Which of the following statements about osmosis is correct?

Accepted Answer

Osmosis is the movement of water across a selectively permeable membrane from high to low water potential.

Question 20

Which of the following would most likely occur if a plant cell is placed in an isotonic solution?

Accepted Answer

The cell will become flaccid due to lack of net water movement.

Passive Transport and Osmosis in Cells: Mechanisms and Effects

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