Studied by 3 people
Define diffusion and eg
The passive movement of a substance from areas of high concentration to an area of low concentration e.g. perfume in a room
Define osmosis and eg
movement of water molecules from an area of low concentration to high concentration across a partially permeable membrane
Define active transport and eg
Movement of a substance from a lower conentration to a higher concentration against the concentration gradient, using energy e.g. mineral absorption by roots
Define surface area to volume ratio and e.g.
The surface area divided by the volume expressed a a ratio e.g. villi in the intestines
Factors that affect the rate of osmosis/ diffusion
High or low concentration gradient, temperature, surface area of membrane. High speeds up. Low slows down
