BIO 110 Quiz #5

 

1.               Plasmodesmata are cell junctions that are similar in function to

a.

gap junctions in animal cells.

b.

tight junctions in animal cells.

c.

adhering junctions in animal cells.

d.

the cuticle in plant cells.

 

2.  If a plasma membrane were compared to a sandwich, ____ would be considered the filling.

a.

cholesterol

b.

protein

c.

hydrophilic heads

d.

hydrophobic tails

e.

carbohydrates

 

3.  .            Cholesterol

a.

is not found in plant membranes.

b.

is a phospholipid.

c.

at high concentrations tends to make fatty-acid tails stick together.

d.

renders membranes more fluid in cold temperature. (it does this a little as well)

e.

all of these

 

4.               Glycolipids differ from other membrane lipids in that they

a.

have hydrophilic heads.

b.

have hydrophobic heads.

c.

have molecules of an oligosaccharide associated with them.

d.

have saturated and partially unsaturated tails.

e.

are stationary molecules found scattered throughout the membrane.

 

5.         A  hormone is most likely bind to which of the following membrane proteins?

a.

Intergin

b.

Recognition

c.

Receptor (signal transduction)

d.

Communication

e.

Transport

 

6.               Which of the following proteins requires ATP for its functioning?

a.

recognition protein

b.

 glycoprotein

c.

active transporter protein

d.

passive transporter protein

e.

integrin protein

 

 

7 .              The rate of diffusion through a selectively permeable membrane will be lowest when which of the following is(are) true?

 

I.

Concentration gradients are steep.

II.

Temperatures are low.

III.

Solutes are small molecules.

 

a.

I only

b.

II only

c.

I and III

d.

II and III

e.

I, II, and III

 

8  .             Oxygen, carbon dioxide, and other small nonpolar molecules cross the plasma membrane through the process(es) of

a.

osmosis.

b.

diffusion. (directly through the membrane without the help of transport proteins)

c.

endocytosis and exocytosis.

d.

active transport.

e.

facilitated diffusion.

 

9.   When physicians perform an organ transplant, they choose a donor whose tissues match those of the recipient as closely as possible. Which of the following cell components are being matched?

A) plasma membrane phospholipids

B) plasma membrane transport proteins

C) cell-surface glycolipids and glcoproteins

D) plasma membrane cholesterols

E) cytoskeletal elements

 

10.  Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of

A) exocytosis.

B) phagocytosis.

C) passive transport.

D) active transport.

E) endocytosis.

 

11.  When two aqueous solutions that differ in solute concentration are placed on either side of a semi-permeable membrane and osmosis is allowed to take place, the water will

A) exhibit a net movement to the side with lower water concentration.

B) exhibit a net movement to the side with higher water concentration.

C) exhibit a net movement to the side with lower solute concentration.

D) exhibit an equal movement in both directions across the membrane.

E) not cross the membrane.

 

12.   A cell that neither gains nor loses water when it is immersed in a solution is

A) isotonic to its environment.

B) hypertonic to its environment.

C) hypotonic to its environment.

D) metabolically inactive.

 

13.   If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference?

A) the expulsion of water by the plant cell's central vacuole

B) the relative impermeability of the plant cell membrane to water

C) the relative impermeability of the plant cell wall to water

D) the fact that plant cells are isotonic to tap water

E) the relative inelasticity and strength of the plant cell wall

14.  In the lab, you use a special balloon that is permeable to water but not sucrose to make an "artificial cell." The balloon is filled with a solution of 20% sucrose and 80% water and is immersed in a beaker containing a solution of 40% sucrose and 60% water. The solution in the balloon is ________ relative to the solution in the beaker.

A) isotonic

B) hypotonic

C) hypertonic

D) hydrophobic

E) hydrophilic

 

15.  Facilitated diffusion across a biological membrane requires ________ and moves a substance ________ its concentration gradient.

A) energy and transport proteins . . . down

B) energy . . . down

C) transport proteins . . . down

D) energy and transport proteins . . . against

E) transport proteins . . . against

 

16.  Which of the following processes can move a solute against its concentration gradient?

A) osmosis

B) passive transport

C) diffusion

D) facilitated diffusion

E) active transport

 

17.  Which of the following is a typical feature of an ATP-driven active transport mechanism?

A) The transport protein must cross to the correct side of the membrane before the solute can bind to it.

B) The solute must be phosphorylated before it can bind to the transport protein.

C) The transport protein is irreversibly phosphorylated as transport takes place.

D) The transport protein catalyzes the conversion of ADP to ATP.

E) The transport protein must be phophorylated to move the solute against the concentration gradient.

18.   The process of a white blood cell engulfing a bacterium is

A) osmosis.

B) diffusion.

C) receptor-mediated endocytosis.

D) pinocytosis.

E) phagocytosis.