Cypress College » Biology » Biology 241 - Accelerated General Human Physiology » Summer 2021

Question #1

If a solute concentration gradient is established across a membrane, the permeable solute will diffuse across the membrane:

A. so slowly that it will result in no net movement

B. in both directions, so that there is no net movement

C. from the area of low concentration to the area of high concentration

D. from the area of high concentration to the area of low concentration

Question #2

In biological systems, membrane channels are usually permeable to:

A. all ions

B. one or a few specific ions

C. only water

D. all hydrophilic molecules

Question #3

When diffusion has stopped, we say the solution has reached:

A. equilibrium

B. net diffusion

C. homeostasis

D. isotonicity

Question #4

Molecules need a carrier protein to help move across a membrane because:

A. they are lipid soluble

B. they are lipid insoluble

C. they are lipid insoluble or they are too large

D. they are too small

Question #5

Most cells:

A. have many sodium channels so sodium freely moves across the membrane

B. have very few sodium channels

C. have sodium channels that are always open

D. have no channels in their membrane

Question #6

When a red blood cell is placed in hypotonic (very dilute) solutions of NaCl:

A. sodium ions rush into the cell, down the concentration gradient

B. some sodium ions may enter the cell

C. sodium ions rush out the cell, down the concentration gradient

D. some sodium ions may leave the cell

Question #7

Glucose travels into absorptive cells of the small intestine:

A. cotransport (symport) with potassium

B. cotransport (symport) with sodium

C. countertransport (antiport) with sodium

D. countertransport (antiport) with potassium