Movement across membranes

Question 1

Transport of substances across cell membranes occurs via three mechanisms:

Answer 1

Active transport, diffusion, and osmosis

Question 2

Diffusion [does/doesn’t] require the use of energy?

Answer 2

Diffusion DOESN’T require the use of energy?

Question 3

Diffusion

Answer 3

The movement of substances from an area of high concentration to an area of low concentration

Question 4

Rate of diffusion can be increased by:

Answer 4

• Increases difference in concentration
• Increase in temperature
• Greater surface area available for diffusion

Question 5

Diffusion occurs until…

Answer 5

…an concentration equilibrium is established

Question 6

Osmosis

Answer 6

The movement of water across a partially permeable membrane from an area of high to low water potential.

Question 7

Water molecules move by osmosis down a…

Answer 7

…water potential gradient

Question 8

Which organ controls the concentrations of ions in the tissue fluid?

Answer 8

The kidneys

Question 9

Active transport

Answer 9

The active pumping of substances against a concentration gradient