Excitable Membranes Flashcards
Where is Na+ (sodium) concentration highest?
Outside the cell
Where is Cl- (chloride) concentration highest?
Outside the cell
Where is K+ (potassium) concentration the highest?
Inside the cell
What are the 4 classes of phospholipids?
- Phosphatidylethanolamine
- Phosphatidylcholine
- Phosphatidylserine
- Phosphatidylinositol
How are the 4 classes of phospholipids classified?
Based on head group composition
What does a long, saturated tail composition of phospholipids mean?
Tighter packing & less fluid
What does a short, unsaturated phospholipid tail composition mean in terms of fluidity?
Loose packing & more fluid
What are sphingolipids?
Same as phospholipids but instead of glycerol neck group it’s serine
What are the 2 classes of sphingolipids?
Sphingomyelin & glucoceramide
How do large uncharged polar molecules, ions and charged polar molecules cross the membrane?
Through the use of integral proteins on the cells membrane
What are ankyrins?
A family of proteins that mediate the attachment of integral membrane proteins to the spectrin-actin based membrane cytoskeleton; aggregates sodium charnels at axon hillock
What are G proteins?
A family of proteins that act as molecular switches inside cells and are involved in transmitting signals from a variety of stimuli outside a cell to its interior; coupled with ligand receptors
What is the significance of glutamate in excitable membranes?
It is a 1° excitatory neurotransmitter in the CNS. it is a fast response neurotransmitter.
