3.2 Chemical Events at the Synapse

Question 1

Amino acids

Answer 1

Acids containing an amine group (NH2)

Question 2

Monoamines

Answer 2

Chemicals formed by a change in certain amino acids

Question 3

Acetylcholine

Answer 3

(A one-member “family”)

A chemical similar to an amino acid, except that it includes an N(CH3)3 group instead of an NH2

Question 4

Neuropeptides

Answer 4

Chains of amino acids

Question 5

Purines

Answer 5

A category of chemicals including adenosine and several of its derivatives

Question 6

Gases

Answer 6

Nitric oxide and possibly others

Question 7

Nitric oxide

Answer 7

Chemical formula NO, a gas released by many small local neurons.

NB! Do not confuse nitric oxide, NO, with nitrous oxide, N2O, aka “laughing gas”

Question 8

MAO (monoamine oxidase)

Answer 8

Enzyme that converts catecholamines and serotonin into synaptically inactive forms

Eg. Several antidepressant drugs inhibit MAO

Question 9

Exocytosis

Answer 9

A release of neurotransmitter from the presynaptic neuron into the synaptic cleft that seperates one neuron from another

Question 10

Ionotropic effects

Answer 10

Synaptic effects that depend on the rapid opening of some kind of gate in the membrane

Question 11

Transmitter-gated or ligand-gated channels

Answer 11

Ion channel that opens temporarily when a neurotransmitter binds to it

Question 12

Metabotropic effect

Answer 12

A sequence of metabolic reactions that produce slow and long-lasting effects at a synapse

Question 13

G-protein

Answer 13

A protein coupled to guanosine triphosphate (GTP), an energy-storing molecule

Question 14

Second messenger

Answer 14

A chemical that, when activated by a neurotransmitter, initates communication to many areas within the neuron

Question 15

Neuropeptide Y (NPY)

Answer 15

Peptide that blocks the satiety actions of the paraventricular nucleus

Question 16

Neuromodulators

Answer 16

Researchers often refer to neuropeptides as neuromodulators, because they can influence the function of neurons but do not act as neurotransmitters

Question 17

Neurogliaform cell

Answer 17

A kind of neuron that releases huge amounts of GABA all at once, producing widespread inhibition

Question 18

Hormone

Answer 18

Chemical that is secreted by cells in one part of the body and conveyed by the blood to influence other cells

Question 19

Neurotransmitters

Answer 19

Chemicals released by neurons that affect other neurons

Question 20

Endocrine glands

Answer 20

Hormone-producing glands

Question 21

Protein hormones

Answer 21

Hormones composed of long chains of amino acids

Question 22

Peptide hormones

Answer 22

Hormones composed of short chains of amino acids

Question 23

Pituitary gland

Answer 23

An endocrine gland attached to the base of the hypothslamus

Question 24

Anterior pituitary

Answer 24

Portion of the pituitary gland, composed of glandular tissue

Question 25

Posterior pituitary

Answer 25

Portion of the pituitary gland, which releases hormones synthesized by the hypothalamus

Question 26

Oxytocin

Answer 26

Hormone released by posterior pituitary; important for sexual and parental behaviours

Question 27

Vasopressin

Answer 27

Antidiuretic hormone. Hormone released by posterior pituitary; raises blood pressure and enables kidneys to conserve water

Question 28

Releasing hormone

Answer 28

Hormone released by the hypothalamus that flows through the blood to the anterior pituitary

Question 29

Acetylcholinesterase (a-SEE-til-ko-lih-NES-teh-raze)

Answer 29

An enzyme that breaks down the neurotransmitter acetylcholine into two fragments: acetate and choline

Question 30

Reuptake

Answer 30

Reabsorption of a neurotransmitter by the presynaptic terminal

Question 31

Transporters

Answer 31

Special membrane protein where reuptake occurs in the neurotransmitter

Question 32

COMT (catechol-o-methyltransferase)

Answer 32

Enzyme that breaks down exess dopamine into inactive chemicals that cannot stimulate the dopamine receptores

Question 33

Autoreseptors

Answer 33

Receptors that respond to the released transmitter by inhibiting futher synthesis and relase. That is, they provide negative feedback

Question 34

Gap junction

Answer 34

A direct contact of one neuron with another, enabling electrical transmission