. Diffusion- movement of particles from a high to low conc gradient
. Active transport movement of particles from a low to high conc gradient, requires energy to do so (Respiration, mitochondria, ATP)
. facilitated diffusion- Along
concentration gradient, no energy, requires external proteins to allow the molecule it to pass through.
. Osmosis- movement of water molecules from a high to low conc gradient
Fluid mosaic model
. Phospholipids can move
.Proteins distributed throughout membrane
.small molecules that are non polar can diffuse through gaps in the membrane aswdll as cat soluble molecules
. Big and polar molecules pass through via proteins, other forms of transport (active transport + fasciliatated diffusion) and hydrophilic pores
Cholestrol
. More cholesterol = membrane less permeable at higher temp
. Cholesterol is a phospholipid that has a fatty acid structure instead of just a chain, it is thicker and less flexible so causes the membrane to be less fluid
