Plasma membrane Flashcards
What is the structure of the PM
phospholipids, 2 fatty acids linked by an ester bond to glycerol
How does the PM form a bilayer
phospholipids are amphipathic
What are the 2 classes of proteins found in PM
integral proteins and peripheral
Where are integral proteins
embedded in the membrane held there by hydrophobic force
Where are peripheral proteins
attached to the surface of PM
What is the fn of the PM
selectively permeable barrier, lipid portion of bilayer excludes most hydrophilic molecules and ions.
How do hydrophilic molecules and ions pass through
by specific integral proteins called transporters. or permeases
PM also have roles in:
respiration, photosynthesis and receptors
What is diffusion
molecules move down its [gradient], can be done into or out of cell, no nrg required
Name molecules that can diffuse across lipid portion
oxygen, CO2, small, unchareged non polar molecules
How does water diffuse through lipid portion of bilayer
specialized pores
