Flashcards in M&R Session 1- The Membrane Bilayer Deck (8)
What are the five functions of biological membranes?
-continuous, highly selective permeable barrier
-control a chemical environment
-communication- between cells and their environment
-recognition- signalling molecules, adhesion proteins and immune surveillance
-signal generation- in response to a stimulus.
What is the dry weight membrane composition?
(20% water as membranes are hydrated structures)
What is the composition of a phospholipid?
Glycerol, 2 fatty acid side chains, a phosphate head group
How do fatty acids increase phospholipid membrane fluidity?
Unsaturated fatty acids contain a cis double bond which produce a kink. This reduces tightness of phospholipid packing and therefore increases membrane fluidity.
What does amphipathic mean?
Both hydrophobic and hydrophilic moieties
What four mobilities do membrane lipids have?
-lateral diffusion within the bilayer
What is the role of cholesterol within a membrane?
To stabilise it!