AS Biology- Cell physiology

Diffusion

The net movement of a substance from where it is in an area of high concentration to an area of low concentration

Endocytosis

Movement of substances into the cell

Exocytosis

The movement of substances out of the cell

Phagocytosis

Involves transport of solid material into the cell

Pinocytosis

Involves transport of fluid into the cell

Osmosis

The net movement of water from an area of high water potential to an area of low water potential through a selectively permeable membrane

Aquaporins

Special channel proteins used to move water through the phospholipid bilayer

Hypertonic

Stronger solution

Hypotonic

Weaker solution

Water potential

A solutions’ tendency to take in water by osmosis from pure water across a selectively permeable membrane

Solute potential

Potential of a solution to take in water only looking at solute concentration

Pressure potential

This is the effect that pressure has on the solution

Water potential equation

Water potential = solute potential + pressure potential

Protoplast

Term used to describe the cytoplasm and vacuole and surrounding cell membrane

Lysis

The expansion of the cell membrane until it breaks

Crenation

If animal cells are placed in a hypertonic solution cells will lose water by osmosis, shrink and shrivel up