Chapter 4 Study Questions

Question 1

What are the six formal criteria for establishing that a particular chemical serves as a neurotransmitter?

1. The chemical exists in _______ terminals.
2. The _______ used to synthesize the chemical are found in presynaptic neurons.
3. The chemical is released when _______ potentials arrive in sufficient quantities to have postsynaptic effects.
4. The postsynaptic membrane contains _______ for the chemical.
5. Experimental application of the chemical also changes postsynaptic _______ .
6. Blocking release of the chemical prevents presynaptic nerve impulses from altering the _______ activity of the cell.

Answer 1

1. PREsynaptic
2. ENZYMES
3. action
4. receptors
5. POTENTIALS
6. POSTSYNAPTIC

Question 2

A drug that binds to a receptor and blocks the effect that the endogenous neurotransmitter would have is termed a(n) _______ , while a drug that mimics the effect of the endogenous substance is called a(n) _______ . A compound that binds to a receptor and causes it to have an effect opposite to the normal effect of the endogenous compound at that receptor is termed a(n) _______ . Some drugs are _______ ligands—they do not bind at the transmitter’s normal binding site, but rather exert their effects through a(n) _______ site.

Answer 2

antagonist; agonist; INVERSE AGONIST; noncompetitive; modulatory

Question 3

It is misleading (although a fairly common practice) to identify a cell on the basis of its transmitter release (e.g., “cholinergic neuron,” “dopaminergic neuron,” “serotonergic neuron”), because an individual neuron may _______ more than one type of transmitter.

Answer 3

CO-LOCALIZE

Question 4

Acetylcholine (Ach) was first identified as a transmitter in the _______ junction. Large numbers of ACh-producing neurons are found in the basal forebrain region, especially the medial _______ nucleus, the nucleus _______ , and in the nucleus of the _______ band.

Answer 4

NEUROMUSCULAR; SEPTAL; BASALIS; DIAGONAL

Question 5

Muscarinic ACh receptors are _______ and therefore respond _______ than nicotinic receptors. They are blocked by the drug _______ . The loss of cholinergic cells in _______ disease suggests that they are important in learning and memory.

Answer 5

METABOTRIPIC; MORE SLOWLY; ATROPINE; ALZHEIMER’S