Osmosis Flashcards Preview

Chapter 5 Plasma Membranes > Osmosis > Flashcards

Flashcards in Osmosis Deck (13):
1

What is osmosis?

-Diffusion of water across a selectively permeable membrane.
-It is a passive process and doesn't require energy.

2

What is a solute?

-Substance dissolved in a solvent forming a solution.

3

What is water potential?

-Measure of the quantity of water compared to solutes.

4

What is the highest value for water potential?

-0, pure water has a water potential of 0.

5

Why is the highest value for water potential zero?

-Presence of a solute lowers the potential and zero is pure water.

6

What does more negative water potential mean?

-More concentrated.

7

What is the hydrostatic pressure?

-Pressure created by water in an enclosed system.

8

What happens if there is a higher water potential outside of an animal cell?

-Water moves into cell by osmosis.
-Increases hydrostatic pressure which results in membrane stretching and so cell swells and it bursts by an event called cytolysis.

9

What happens if there is a lower potential outside of an animal cell?

-Water moves out of the cell by osmosis.
-Reduction in cells volume and cell membrane puckers and shrinks which is referred to as crenation.

10

What happens if the animal cell and the outside has an equal water potential?

-Water constantly leaves and enters the cell so there is no change in the state of cell.

11

What happens if there is a higher water potential outside a plant cell?

-Water enters cell, increase in hydrostatic pressure which pushes the membrane against the cell wall.
-The cell swells and becomes turgid.

12

What happens if there is a lower water potential inside a plant cell?

-Water leaves plant cell, membrane pulled away from cell wall.
-The cell is plasmolysed.

13

What happens if the plant cell and the outside has the same water potential?

-Water constantly leaves and enters the cell.
-No change in the state of the cell.