Question 1

Which component of the plasma membrane is primarily responsible for its selective permeability?

Accepted Answer

Phospholipid bilayer

Question 2

A red blood cell is placed in a hypertonic solution. What will happen to the cell, and why?

Accepted Answer

It will shrink because water leaves the cell by osmosis.

Question 3

Which of the following best describes the structure of a phospholipid?

Accepted Answer

A molecule with a hydrophilic head and two hydrophobic tails

Question 4

Which equation best represents the movement of molecules during simple diffusion?

Accepted Answer

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

Question 5

Why do ions and polar molecules require transport proteins to cross the plasma membrane?

Accepted Answer

Because the hydrophobic core of the membrane repels them

Question 6

Which of the following is a function of the glycocalyx on the cell membrane?

Accepted Answer

Serving as a biological marker for cell recognition

Question 7

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

Accepted Answer

Cells will burst due to water influx

Question 8

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

Accepted Answer

Active transport

Question 9

The sodium-potassium pump moves sodium and potassium ions against their concentration gradients. Which equation best represents the energy requirement for this process?

Accepted Answer

$$\Delta G \u003e 0$$

Question 10

Which of the following statements about membrane fluidity is correct?

Accepted Answer

Membrane fluidity increases with more unsaturated fatty acid tails

Question 11

Facilitated diffusion differs from simple diffusion in that:

Accepted Answer

Facilitated diffusion uses transport proteins

Question 12

Which of the following is an example of channel-mediated facilitated diffusion?

Accepted Answer

Sodium ions moving through a voltage-gated channel

Question 13

A cell is placed in an isotonic solution. What will happen to the cell?

Accepted Answer

It will remain the same size

Question 14

Which of the following best describes secondary active transport?

Accepted Answer

It uses the energy stored in an ion gradient to transport another molecule

Question 15

Which equation describes the osmotic pressure exerted by a solution?

Accepted Answer

$$\Pi = iMRT$$

Question 16

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

Accepted Answer

Forming the glycocalyx

Question 17

Why do plant cells not burst when placed in hypotonic solutions?

Accepted Answer

Because they have a strong cell wall that limits expansion

Question 18

Which of the following would most likely increase the fluidity of a cell membrane in cold temperatures?

Accepted Answer

Increasing the proportion of unsaturated fatty acids

Question 19

A mutation causes the glycocalyx of a cancer cell to change rapidly. What is a likely consequence?

Accepted Answer

The cell will be protected from immune detection

Question 20

Which of the following best explains why steroid hormones can easily cross the plasma membrane?

Accepted Answer

They are nonpolar and lipid-soluble

Membrane Structure and Transport: Study Notes for General Biology

Guida di studio - Domande di pratica

Study guide - Flashcard