1. List four neurotransmitters that bind to ion channels, these neurotransmitters are called __directly____-acting neurotransmitters.
2. a. The binding of ACh opens ion channels in the dendrites or cell body that permits both _sodium______ and _potassium____ to move through them.
b. Which ion would move into the cell? _sodium____out of the cell?
c. Which ion has the greatest electrochemical gradient? _sodium______
d. The net movement of these two ions would do what to the cell?
e. This would be called an ____excitatory________ postsynaptic potential, or __epsp__________________.
3. a. An inhibitory postsynaptic potential (IPSP) causes a neuron to
b. An example of a neurotransmitter that causes an IPSP is ___gaba___________.
c. What type of ions move into the cell in response to this neurotransmitter?
4. a. Norepinephrine binds to a receptor that is separate from the ion channel. This is known as a/an _____indirectly__ - acting neurotransmitter.
b. Norepinephrine is known as the ____first_________ messenger.
c. The receptor is coupled to the ion channel by a ___G protein________________.
5. a. This activates an enzyme which induces the production of a
b. An intracellular enzyme is activated and ___phosphorylate_________________ the ion channel.
c. As a result of this sequence of events, what channels are closed?
d. What does this do to the neuron? __depolarizes______
6. Name three neurotransmitters that can only act indirectly.
7. Which of the four neurotransmitters mentioned in question 1 can also act indirectly?
8. Which one of the four neurotransmitters mentioned in question 1 can only act directly?