Cell Biology Essentials: Energy, Transport, and Metabolism

Cell Structure and Membrane Transport

9) Which component is a microfilament (actin filament) of the cytoskeleton?

C

10) Which component is a glycolipid?

B

11) Which of the following most accurately describes selective permeability?

Only certain molecules can cross a cell membrane.

12) Which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly?

CO2

13) Which of the following allows water to move much faster across cell membranes?

Aquaporins

14) Diffusion _____.

Is a passive process in which molecules move from a region of higher concentration to a region of lower concentration.

15) Which of the following is true of osmosis?

In osmosis, water moves across a membrane from areas of lower solute concentration to areas of higher solute concentration.

17) The sodium-potassium pump is called an electrogenic pump because it _____.

Contributes to the membrane potential.

22) The force driving simple diffusion is _____, while the energy source for active transport is _____.

The concentration gradient; ATP.

23) White blood cells engulf bacteria using _____.

Phagocytosis.

25) The difference between pinocytosis and receptor-mediated endocytosis is that _____.

Pinocytosis is nonselective in the molecules it brings into the cell, whereas receptor-mediated endocytosis offers more selectivity.

Chapter 6: Cell Energy, Transport, and Enzymes

1) Kinetic energy differs from chemical energy in that:

Kinetic energy is the energy of a moving object, whereas chemical energy is the potential energy of molecules.

2) Glucose molecules provide energy to power the swimming motion of sperm. In this example, the sperm are changing:

Chemical energy into kinetic energy.

3) According to ________, energy cannot be created or destroyed.

The first law of thermodynamics.

4) Which of the following energy transfers is impossible in living systems?

Heat to light energy.

5) Which of the following processes is endergonic?

The synthesis of glucose from carbon dioxide and water.

6) What is the basic difference between exergonic and endergonic reactions?

Exergonic reactions release energy; endergonic reactions absorb it.

7) Which of the following examples is classified as a metabolic pathway?

Protein synthesis.