chapter 8 multiple choice

Question 1

Glycoproteins and glycolipids are important for

Answer 1

Cell-cell recognition

Question 2

A single layer of phospholipid molecules coats the water in a beaker. Which part of the molecules will face the air

Answer 2

The hydrocarbon tails

Question 3

Support for the fluid mosaic model of membrane structure comes from

Answer 3

All of the above

Question 4

A freshwater paramecium is placed into salt water. Which of the following events would occur?

Answer 4

Shriveling of the cell

Question 5

Ions diffuse across membranes down their

Answer 5

Electrochemical gradient

Question 6

The fluidity of membranes in a plant in cold weather may be maintained by

Answer 6

Increasing the number of phospholipids with unsaturated hydrocarbon tails

Question 7

A plant cell placed in a hypotonic environment will

Answer 7

Become turgid

Question 8

The membrane potential of a cell favors the

Answer 8

Movement of cations into the cell

Question 9

Cotransport may involve

Answer 9

Transport of one solute against its concentration gradient in tandem with another that is diffusing down its concentration gradient

Question 10

Exocytosis involves all of the following except

Answer 10

Ligands and coated pits

Question 11

The proton pump in plant cells is the functional equivalent of an animal cell’s

Answer 11

Sodium potassium pump

Question 12

Pinocytosis involves

Answer 12

The pinching in of the plasma membrane around small droplets of external fluid

Question 13

Watering a houseplant with too concentrated a solution of fertilizer can result in wilting because

Answer 13

The soil solution becomes hypertonic, causing the cells to lose water

Question 14

Initially the solution in side a with respect to that in side b, is

Answer 14

Isotonic

Question 15

After the system reaches equilibrium, what changes are observed?

Answer 15

The water level is higher in side a than in side b

Question 16

During the period before equilibrium is reached, which molecules will show net movement through the membrane?

Answer 16

Water and glucose

Question 17

Facilitated diffusion across a cellular membrane requires —– and moves a solute —– its concentration gradients

Answer 17

Transport proteins —– down

Question 18

The fluid mosaic model describes biological membranes as consisting of

Answer 18

A phospholipid bilayer with proteins embedded in and attached to it

Question 19

You observe plant cells under a microscope that have just been placed in an unknown solution. First the cells plasmolyze; after a few minutes, the plasmolysjs reverses and the cells appear normal. What would you conclude about the unknown solute?

Answer 19

It is hypertonic to the plant cells, but it’s solute can cross the plant cell membranes