Module 3.2

Question 1

What did T.R. Elliot propose?

Answer 1

that the sympathetic nerves stimulate muscles by releasing adrenaline or a similar chemical

Question 2

Describe Loewi’s experiment with the two frogs’ hearts.

Answer 2

Loewi stimulated the vague nerve in one of the frog’s heart, which decreased the frog’s heart rate. Then, he collected fluid from that heart and transferred it to the other frog’s heart. That heart also decreased its rate of beating. After this he did the exact same thing except this time he stimulated the accelerator nerve, which increased both heart’s rate of beating. He concluded that stimulating one nerve released a chemical that inhibited heart rate and stimulating another nerve released a chemical that increased heart rate.

Question 3

Summarize the events occurring at the synapse in your own words.

Answer 3

*

Question 4

How is nitric oxide unlike most other neurotransmitters?

Answer 4

it is not an amino acid

Question 5

What is nitric oxide’s main function?

Answer 5

to send a message to your blood when a part of your brain becomes more active, causing blood flow to increase to that area

Question 6

How might one increase the amount of acetylcholine in the brain?

Answer 6

by eating milk, eggs, and peanuts

Question 7

How might one increase the amount of serotonin in the brain?

Answer 7

by eating foods that are rich in tryptophan, such as soy

Question 8

How are neurotransmitters typically stored?

Answer 8

by the presynaptic terminal in vesicles

Question 9

Describe the process of neurotransmitter release (exocytosis).

Answer 9

Neurotransmitters are released in bursts from the presynaptic neuron into the synaptic cleft that separates the neuron from the postsynaptic neuron.

Question 10

What is a neuromodulator?

Answer 10

substances that do not directly activate ion-channel receptors but that, acting together with neurotransmitters, enhance the excitatory or inhibitory responses of the receptors

Question 11

What are autoreceptors? What is their function?

Answer 11

Receptors that detect the amount of transmitter released and inhibit further synthesis and release it after it reaches a certain level. Their main function is to provide negative feedback.

Question 12

What is the function of chemicals released by the postsynaptic cell that travel back to the presynaptic terminal?

Answer 12

To control or limit he postsynaptic neuron input

Question 13

What happens to acetylcholine, serotonin, and the catecholamines after they detach from receptors?

Answer 13

The presynaptic neuron takes up most of the released neuroransmitter molecules intact and reuses them (reuptake)