Chapter 2: Synapses and Neuronal Impulses Flashcards
What happens in a graded electrical potential?
Binding of neurotransmitters to the synapse, this pens porous channels within the membrane where negative and positive ions can pass through. The amount of positive versus negative ions can change whether the response is positive or negative.
What happens if a graded electrical impulse is positive enough?
Axon will generate an action potential
What are the steps to the reaction of excitatory /inhibitory neurons?
- An action potential shoots down the axon.
- Neurotransmitters are released into the synapse, changing the membrane potential of the dendrite.
- If the depolarization is strong enough, it spreads down the dendrite and across the cell body
- If threshold is reached, the cell fires, shooting an action potential down the axon
What is the point at which excitatory and inhibitory inputs are integrated?
The axon hillock
Who is Luigi Galvani?
In 1791 Luigi Galvani discovered the concept of bio electricity while investigating static electricity.
The nerves of the frog legs were threaded with copper wire but Galvani still assistant accidentally touched an exposed sciatic nerve with a metal scalpel, which had picked up a charge.
A spark snapped and the legs jerked violently (galvanized into action) demonstrating a closed electrical circuit
How many kinds of molecule can pass through each pore?
Only one kind of molecules, charge, etc.
What is the electrical potential of the membrane at rest?
-70 mv
What is an electrical potential?
It is the difference in electrical charge inside relative to outside the cell.
The membrane of a neuron maintains an electrical potential
What are protein channels and where are they located?
They are embedded in the membrane of a cell and permit certain ions to cross through the membrane at a controlled rate.
How can the membrane electrical potential be measured?
With a voltmeter
