Transport

Diffusion:High to low
concentration

Simple:Unassisted diffusion of solutes
through the plasma membrane

Osmosis: The diffusion of water through
the membrane. Aquaporin makes it easier
for water to get through

Facilitated: Diffusion of substances using
a protein membrane channel

Used because the solid is too large or lipid
insoluble

Filtration: Process by which water
and solutes are forced through a
a membrane by fluid pressure

Hydrostatic pressure is usually exerted
by blood. A pressure hradient pushes
solute-containing fluid from the higher-pressure
area to the lower-pressure area.

Ex: Kidneys

Solute Pumps: Protein carriers that
combine reversibly with the solute
and use ATP

Examples of this are sodium-potassium pumps.
They simultaneously carry sodium ions out and
potassium ions into the cell. This is necessary
for the transmission of the nerve impulses

Bulk Transport: includes exocytosis
and endocytosis

Exocytosis moves substances out of cells packaging
them into vesicles

Phagocytosis: Cytoplasmic extensions engulf large
particles such as bacteria or dead body cells

Endocytosis moves substances into the cell by
packaging them into vesicles

Pintocytosis: The cell membrane takes in a droplet of
extracellular fluid containing dissolved proteins or fats