Neurophysiology basics + Membrane ion chanels

Question 1

Describe Action Potential

Answer 1

An Electrical event in the neuron where the neuron membrane changes from an area of postive to negative and back to negative.
-this AP is an electrical impulse that travels down length of neuron to another cell

Question 2

POSTIVE sodium ions are in high concentration _______ the cell and want to move _______ the cell.

Answer 2

sodium ions are in high concentration OUTSIDE the cell and want to move INSIDE the cell.

Question 3

POSTIVE Potassium ions are in high concentration _______ the cell and want to move _______ the cell.

Answer 3

Potassium ions are in high concentration INSIDE the cell and want to move OUTSIDE the cell.

Question 4

outside the cell what are there larged amounts of?

Answer 4

negative chloride ions

Question 5

inside the cell what are there large amounts of?

Answer 5

negativiely charged proteins

Question 6

First of all, what are membrane ion channels?

Answer 6

Membrane protiens

Question 7

Describe a Leak Channel

Answer 7

-memebrane proteins that include passive transport (no energy) of differnt substances
-ALWAYS open. 7/11 of channes.
-go down concentration gradient
-specific to each ion!!

Question 8

Describe Gated Channels and what are the three main types?

Answer 8

Gated channels are membrane proteins that allow ions to pass though only during certain circumstances.
-REQUIRES ENERGY!!

3 types
1.chemically gated
2.Voltage gated
3.mechanically gated

Question 9

Chemically gated channels

Answer 9

open only if a chemical (like a neurotransmitter) binds to the membrane protien.

Question 9

Voltage gated channels:

Answer 9

-rely on change on membrane potential. (ELECTRICAL change)
-there is usally a voltage setting when they open and a voltage setting when they close.
-exampels: K+, Na+, and CA+ channels

Question 10

Mechanically gated channels

Answer 10

-open or close in response to a physical distrortion (pressure).
ex: Sensory receptors for touch