Bio: Neurotransmission

Question 1

Neurons

Answer 1

Nerve cells

Question 2

Neurotransmitter

Answer 2

A neurotransmitter is a chemical messenger that carries signals between neurons. Neurotransmitters are released from the terminal buttons at the end of an axon after the action potential has sent an electrical charge down the neuron. The neurotransmitter then crosses the synaptic gap to reach the receptor site on another neuron.

Question 3

Excitatory Function

Answer 3

These types of neurotransmitters increase the likelihood that the neuron will fire an action potential. It is also when a drug attaches to a receptor site for a neuron and activates the neuron as if the neurotransmitter was sending a message.

Question 4

Inhibitory Function

Answer 4

When a neurotransmitter decreases the likelihood that the neuron will fire an action potential. It may also be when a drug attaches to a receptor site for a neurotransmitter and blocks the transmission across the synapse.

Question 5

Soma

Answer 5

The main cell body of a neuron

Question 6

Axon

Answer 6

The long, threadlike part of a nerve cell that transfers the nerve impulse

Question 7

Terminal Buttons

Answer 7

Tiny bulblike structures at the end of the dendrites, which contain neurotransmitters that carry the neuron’s message into the synapse.

Question 8

Synaptic Gap

Answer 8

The space between 2 nerve cells

Question 9

Dendrite

Answer 9

The branched projections of a neuron that receive the message from the terminal buttons of the previous nerve cell.

Question 10

Receptor Site

Answer 10

Areas on the dendrite where the neurotransmitters bind in order to pass along the signal

Question 11

Re-uptake

Answer 11

The reabsorption of a neurotransmitter by the terminal buttons of the pre- synaptic neuron after it has performed its function of transmitting neural impulses. This prevents further activity of the neurotransmitter.

Question 12

Serotonin

Answer 12

A neurotransmitter that works to regulate mood, appetite, and sleep. Low levels of serotonin have been linked to Clinical Unipolar depression and high levels of aggression. High levels of serotonin have been linked to
hallucinations.

Question 13

Dopamine

Answer 13

A neurotransmitter that helps control the brain’s reward and pleasure centers. Dopamine also helps regulate emotional responses. Dopamine deficiency results in Parkinson’s Disease, and people with a lower number
of dopamine receptor sites may be more prone to addiction.

Question 14

Acetylcholine (ACh)

Answer 14

The most common neurotransmitter. Acetylcholine receptor sites are found in the hippocampus. It appears that acetylcholine plays a key role in memory consolidation from STM to LTM.

Question 15

Agonist

Answer 15

Chemicals that enhance the action of a neurotransmitter.

Question 16

Antagonist

Answer 16

A chemical or drug that blocks or inhibits the action of the neurotransmitter, usually by binding at the receptor site so the neurotransmitter cannot.

Question 17

Scopolamine

Answer 17

A drug that acts as an antagonist to ACh

Question 18

MAO-A (Monoamine

Oxidase A)

Answer 18

An enzyme that helps break down neurotransmitters (like dopamine, norephinephrine, and serotonin) that remain in the synaptic gap after binding and re-uptake has occurred.

Question 19

Neurotransmitter SAQ intro

Answer 19

Introduction:

• Neurotransmitters are chemicals that carry the electrical impulses between neurons in the brain and body
• they act within the gap between two neurons, the synapse
• very fast process
• starts in dendrites that branch out form the cell body and receive electrochemical impulses from a nearby neuron
• the impulse passes down the axon as an action potential, down to the terminal buttons, which contain tiny sacs filled with a neurotransmitter called a synaptic vesicle.
• the neurotransmitter is then released into the synapse between the neurons
• synapses can be excitatory or inhibitory, which means they can either instruct the receiving neuron to fire or not to fire respectively.
• each nuerotransmitter can act in either an excitatory way or an inhibitory way
• neutrotransmitters are affected by chemicals that bind to receptor sites, agonists which increase the neurotransmitter effect, or antagonist, which reduce their effect