topic 3 - movement across cells Flashcards
1
Q
what is diffusion?
A
the movement of molecules from an area of high concentration to an area of low concentration
2
Q
what is osmosis?
A
the movement of water molecules from an area of high concentration to an area of low concentration through a partially permeable membrane.
3
Q
what is active transport?
A
the movement of a substance from and area of low concentration to an area of hight concentration. this requires energy as it is moving against the concentration gradient.
4
Q
what are some factors affecting the rate of diffusion?
A
- temperature
- surface area
- distance
- concentration gradient