Particles move from an area of high
concentration to low
Anotações:
For example, different gases can simply diffuse through one another. Alternatively, dissolved particles can diffuse in and out of cells through cell membranes.
The structure of leaves let gases diffuse in and out of cells
Diffusion through cell membranes
Gas exchange happens in the lungs
The villi provide a really really big
surface area
Osmosis
Similar to diffusion, but only refers to water
Water moves across a partially permeable membrane (eg. cell membrane)
from an area of high water concentration to low
Active Transport
Root hairs are specialised for
absorbing water and minerals
Sometimes substances need to be
absorbed against a concentration gradient
- ie. from a lower to higher concentration
Root hairs take in minerals
using active transport