Cellular communication Flashcards
What is the plasma membrane?
Thin layer of lipids and proteins that maintains the boundary between intracellular and extracellular fluids
Phospholipids are amphiphilic, what does this mean?
They have a hydrophilic and hydrophobic end
How do animal membranes adapt to a change in temperature?
Warm adapted- Saturated fatty acids
Cold adapted- Polyunsaturated fatty acids
What are the 4 major phospholipids?
Phosphatidylethanolamine
Phosphatidylserine
Phosphatidylcholine
Sphingomyelin
What is lipid asymmetry?
The different distribution of phospholipids in each bilayer
What is phosphatidylinositol?
Phospholipid in the cytosolic monolayer important for cell signalling
Phospholipids, cholesterol and glycolipids are classes of what?
Lipid membranes
What are the 4 types of cellular communication?
Gap junctions
Signalling molecules on surface
Chemical messengers
Extracellular chemical messengers (most common)
What are the 8 chemical messengers?
Gases
Eicosanoids
Purines
Amines
Peptides
Proteins
Steroids
Retinoids
How do signals enter the cell?
Via a carrier protein which diffuses across a receptor to an intracellular receptor protein in the nucleus
G-protein coupled, gated membrane channels and enzyme-coupled are examples of what?
Cell-surface receptors
What is another name for phosphatidylinositol bisphosphate?
PIP2
How is PIP2 cleaved?
Phospholipases activated by GPCRs
What does cleaving PIP2 cause?
Production of molecule fragments acting as short-lived mediators
What communication is dependent on cells being membrane-membrane?
Contact dependent
