2.1.2 Osmosis Flashcards
1
Q
Osmosis
A
Diffusion of water molecules across a selectively permeable membrane
2
Q
Selectively permeable membrane
A
Pores in membrane to let small molecules through
3
Q
Water potential
A
Concentration of free water molecules
4
Q
Plant cell when in concentrated solution, higher water potential
A
- takes up water by osmosis
- turgor pressure increases
- becomes turgid/firm
5
Q
Plant cell when placed in higher concentration, lower water potential
A
- cell loses water
- turgor pressure falls
- cell becomes flaccid(soft)
- becomes plasmolysed (cell contents collapse away from cell)
6
Q
Animal cell when placed in less concentrated, higher water potential
A
- cell takes up water
- cell swells, may burst
- cell lysis
7
Q
Animal cell when placed in more concentrated, low water potential
A
- loses water by osmosis
- cell becomes crenated(crinkles)
8
Q
Cell when placed in same surroundings
A
Cell stays same
No net movement of water
9
Q
Percentage change formula
A
Percentage change= (new result - original result / original result)X100
- positive = percentage gain
- negative= percentage loss
