Membrane Structure & Synthesis Flashcards
what is the purpose of membranes?
to form barriers between cells and within cells
what are membranes made of?
phospholipids
-with polar hydrophilic head group and hydrophobic tail
where are phospholipids synthesised?
SER then transported to golgi
-ATP binding cassette transporter (ABC Transporters) required for phospholipid to enter GA
what does floppase do?
move phospholipids from inner leaflets of the membrane to outer
- flippase does opposite
- scramblers has a bidirectional movement
what are the factors affecting membrane fluidity?
- temperature
- FA composition
- cholesterol content
what occurs in spur cell anaemia?
- cholesterol content 65% higher than average
- leads to decrease in membrane fluidity + flexibility
- affects function of RBC and gets stuck in capillaries and rupture
what is the name of the model that presents how proteins and lipids interact with the membrane?
fluid mosaic model
what are the names of the proteins that are present in the membrane?
- integral membrane proteins
- peripheral membrane proteins
- lipid anchored proteins
what are integral membrane proteins?
- single or multipass proteins
- strong non covalent bonds
- transmembrane proteins
they interact with bolster intensively
what are peripheral membrane proteins?
- locates on the extracellular cystoscope membrane
- associated by non covalent bonds
- easier to remove these proteins
what are lipid anchored membrane proteins?
-covalently linked to a lipid
what are membrane carbohydrates?
- associated w lipids and proteins
- 2-10% of membrane weight
- carbohydrate faces away from cytoplasmic
- involved with cell to cell interactions
- in RBCs= 8% of weight is carbohydrates
