Lecture 2 Flashcards
In the nervous system, cell membranes are important for
- Creating action potentials for muscle contraction
- Ion and water balance both inside and outside the cells
What is the plasma membrane?
Outer layer of the cell that separates the intracellular and extracellular environments
Creating action potentials and osmoregulation depend on the
Movement of molecules from one side of the cell membrane to the other
The rate of Passive Diffusion is the fastest when
The distance is short and concentration gradient is large
Only osmosis / water molecules can pass via
Passive Diffusion
Facilitated Diffusion is done via
Integral proteins
What are Ion Channel Proteins?
Integral membrane proteins that transport molecules
Ion Channels only open when their gates
Encounter specific stimuli
Ion Channel Proteins are classified based on
What causes gate to open / close
Ligand-Gated Ion Channels open or close when
Specific molecules (ligands) bind to channel
Acetylcholine receptor is a Ligand-Gated Sodium Channel involved in
Muscle contraction
Voltage gated Ion channels open or close in response to
A change in electrical charge (voltage) across the membrane
Mechano-Gated Ion Channels open or close in response to
Changes in pressure on the cell membrane
Baroreceptors in blood vessels are examples of
Mechano-Gated Ion Channels
Change in blood pressure opens or closes
Mechano-Gated Ion Channels
