How do substances get in and out of cells?
Dissolved substances move into and out of your cells across the cell membrane.
1) DIFFUSION 2) OSMOSIS 3)ACTIVE TRANSPORT
Happens when particles spread out from higher concentration to lower concentration. This takes place due to the random movement and bumping of particles.
If there is a big concentration difference between two places, diffusion rates will be high. When a substance is moving from higher to lower, it will appear to be slower. This is because some particles will randomly move into lower area, but some will move back into higher through random movement, so takes longer.
Net movement = particles moving in - particles moving out