5 Plasma Membranes Flashcards
Describe the membrane
- made of phospholipid
- approximately 7mm wide
- allows for compartmentalisation within cells
- conserved structure
What are the components of the membrane?
- phospholipids
- proteins
- cholesterol
- receptors
Why is it named “fluid mosaic model”?
- ‘fluid’ as the phospholipids can move relative to each other
- ‘mosaic’ as the surface looks like a mosaic pattern
What are the types of protein that can attach to the membrane?
- active transport/carrier protein
- channel protein
- extrinsic protein (enzymes, antigen, receptor)
Define “glycolipid”
Lipid in the bilayer attaches to a carbon chain
Define “glycoprotein”
Protein in the bilayer attaches to a carbon chain
Difference between intrinsic and extrinsic protein?
Intrinsic goes all the way through the bilayer and extrinsic goes through half of the bilayer
Define “glycocalyx”
Carbon chains attached to bilayer
- recognition
- receptors
- antigen attachment
Types of movement across the membrane?
- passive diffusion
- facilitated diffusion
- active transport
- cotransport
- endo and exocytosis
Define “passive diffusion”
Movement of non-polar, small molecules directly through the bilayer between the phospholipids (O2, CO2)
Define “facilitated diffusion”
Movement of large or charged molecules through open channel proteins (Na+, C6H12O6)
What substances are involved in active transport?
- Na+
- K+
- ATP
