Life 102 Chapter 7 Review Questions

The internal solute concentration of a plant cell is about 0.8M. To demonstrate plasmolysis, it would be necessary to suspend the cell in what solution?

1.0M

Which of the following plant cells would exhibit the most turgor pressure?

A cell placed in a hypotonic solution

Which of the following statements about diffusion is true?

Its a Passive Process

Which of the following is correct regarding peripheral proteins?

These proteins are found only on the surface of the plasma membrane

The sodium-potassium pump __________.

Transports sodium ions out of the cell and transports potassium ions into the cell

Which of the following substances would be most likely to pass through the plasma membrane without the help of a transport protein?

A nonpolar molecule, such as a hydrocarbon

Which of the following is a correct difference between active transport and facilitated diffusion?

Active transport requires energy from ATP, and facilitated diffusion does not

How does cholesterol affect membrane fluidity?

At body temperature, it makes the membrane less fluid.

Why is energy required for active transport?

Because it moves solutes against their concentration gradient

If a red blood cell and a plant cell were placed in seawater, what would happen to the two types of cells?

Both cells would lose water; the red blood cell would shrivel, and the plant plasma membrane would pull away from the cell wall.

Which of the following molecules is most likely to passively diffuse across the plasma membrane?

Carbon Dioxide

In facilitated diffusion, __________ proteins provide openings in the plasma membrane for substances to flow through without changing structure, and __________ proteins allow passage of substances through the plasma membrane after undergoing a subtle change in shape

Channel; carrier

Which of the following processes and organelle(s) accounts for the replacement of lipids and proteins lost from the plasma membrane?

Exocytosis and Smooth and Rough ER

Which of the following statements about passive transport is correct?

Passive transport permits the solute to move in either direction, but the net movement of the population of solute molecules occurs down the concentration gradient of the molecule

Which of the following statements about the role of phospholipids in the structure and function of biological membranes is correct?

Phospholipids form a selectively permeable structure

Which of the following cell structures exhibits selective permeability between a cell and is external environment?

Plasma Membrane

How does the "fluid mosaic model" describe the structure of the plasma membrane?

Proteins in the membrane contribute to the mosaic quality of the membrane while the lateral and rotational movements of phospholipids contribute to its fluidity

A cell is placed into a solution and the cell shrinks. Which of the following is true regarding the solution?

The Solution is hypertonic

The plasma membrane exhibits selective permeability. This means that __________.

the plasma membrane allows some substances to flow through it more easily than others