SS Biology--Osmosis & Diffusion Practice

Diffusion is the movement of molecules from...

• an area of high concentration to an area of low concentration.
• an area of low concentration to an area of high concentration.
• an area of equilibrium to an area of high concentration.

Which means particle transport requires input of energy from the cell?

• diffusion
• active transport
• osmosis

The diffusion of WATER across a selectively permeable membrane is called

• active transport.
• osmosis.
• osmotic pressure.

An animal cell (think raisin) that is surrounded by fresh water will burst because the osmotic pressure causes

• water to move into the cell.
• water to move out of the cell.
• solutes to move out of the cell.

The cell membrane contains channels and pumps that help move materials from one side to the other. What are these channels and pumps made of?

• lipids
• carbohydrates
• proteins

When the concentration of molecules on both sides of a membrane is the same, the molecules will

• move across the membrane to the inside of the cell.
• move across the membrane in both directions.
• stop moving across the membrane.

In isotonic solutions...

• water moves into and out of the cell equally.
• water moves into the cell.
• water moves out of the cell.
• water doesn't move at all.

In hypotonic solutions...

• water moves into and out of the cell equally.
• water moves into the cell.
• water moves out of the cell.
• water doesn't move at all.

In hypertonic solutions...

• water moves into and out of the cell equally.
• water moves into the cell.
• water moves out of the cell.
• water doesn't move at all.

Use Figure 7-3 above to answer the following question. Which beaker is hypertonic?

• A
• B
• C
• None