Biology Chapter 7

is the boundary that separates the living cell from its surroundings

allowing some substances to cross it more easily than others ; the plasma membrane exhibits it

the most abundant lipid in the plasma membrane

phospholipids ; contain hydrophobic and hydrophilic regions

states that a membrane is a fluid structure with a "mosaic" of various proteins embedded in it.

fluid to work properly; they are usually about as fluid as salad oil

can move within the bilayer

collage of different proteins embedded in the fluid matrix of the lipid bilayer

most of the membrane's specific functions

are bound to the surface of the membrane

penetrate the hydrophobic core

one or more stretches of nonpolar amino acids, often coiled into alpha helices

• 1) Transport
• 2) Enzymatic Activity
• 3) Signal Transduction
• 4) Cell-cell Recognition
• 5) Intercellular Joining
• 6) Attachment to the cytoskeleton and extracellular matrix (ECM)