G7_Explorer_Synaptic Transmission and Amino Acid Neurotransmitters

Question 1

the most abundant neurotransmitters in the brain

Answer 1

Amino acids

Question 2

Neurotransmitters are synthesized and stored in ____

Answer 2

presynaptic terminals

Question 3

are specialized biological structures found in
the nervous system; they connect neurons together and transmit signals across
the neurons

Answer 3

Chemical and electrical synapses

Question 4

the primary excitatory neurotransmitter in the brain

Answer 4

Glutamate

Question 5

the principal inhibitory neurotransmitter in the brain

Answer 5

GABA

Question 6

single amino acid residues released from presynaptic nerve terminals in response to an action potential and cross the synaptic cleft to bind with specific receptor on the postsynaptic membrane

Answer 6

glutamic acid, GABA, aspartic acid, and glycine

Question 7

The nervous system is composed of billions of specialized cells called

Answer 7

neurons

Question 8

the cells of chemical communication in the brain

Answer 8

Neurons

Question 9

In its most basic form, a neuron has two ends:

Answer 9

an axon
and a dendrite

Question 10

are chemical substances that act as the mediator for
the transmission of nerve impulses from one neuron to another neuron through
synapses.

Answer 10

Neurotransmitters

Question 11

Neurotransmitters are stored in the axon (or presynaptic neuron) in little packages called ___

Answer 11

synaptic vesicles

Question 12

The release of neurotransmitter is triggered by the arrival of ___

Answer 12

nerve impulse (or action potential)

Question 13

are specialized junctions through which cells of the nervous system signal to one another and to
non-neuronal cells such as muscles or glands

Answer 13

Synapses

Question 14

The process by which the information is communicated through synapse is called

Answer 14

synaptic transmission

Question 15

The secreted neurotransmitters can act on receptors on the membrane of the postsynaptic neuron through a gap called ___

Answer 15

synaptic gap

Question 16

a junction between neurons that allows different molecules and ions to pass freely between cells

Answer 16

gap junction

Question 17

A gap junction is composed of ___

Answer 17

connexons

Question 18

each connexon is composed of ___ connexin proteins

Answer 18

six

Question 19

Synapses between axons and dendrites are called

Answer 19

axodendritic

Question 20

Particularly powerful synapses made between axons of one neuron and cell body of another postsynaptic cell are called ___

Answer 20

axosomatic synapses

Question 21

The three major categories of substances that act as neurotransmitters are:

Answer 21

Amino acids
Amines
Others: The one which do not fit in any of these categories (acetyl choline and
nitric oxide)

Question 22

The neurotransmitters of this group are involved in fast synaptic transmission and are inhibitory and excitatory in action

Answer 22

Amino acids

Question 23

are the modified amino acids

Answer 23

Amines

Question 24

The neurotransmitters of this group involve in slow synaptic transmission and are inhibitory and excitatory in action

Answer 24

Amines

Question 25

noradrenaline, adrenaline, dopamine, serotonin, and histamine are

Answer 25

Amines

Question 26

glutamic acid, GABA, aspartic acid, and glycine are

Answer 26

Amino acids

Question 27

the two amino acids are often are found together at axon terminals

Answer 27

Aspartate glutamate

Question 28

The two amino acids functioning as excitatory neurotransmitter are

Answer 28

Aspartate glutamate

Question 29

acts as a brake to the excitatory neurotransmitters

Answer 29

GABA

Question 30

Neurotransmitters can be classified as either

Answer 30

excitatory inhibitory

Question 31

__ neurotransmitters function to activate the receptors on the postsynaptic membrane and enhance the effects of action potential

Answer 31

Excitatory

Question 32

The action potential is produced by an influx of ___ through voltage dependent calcium-selective ion channels

Answer 32

calcium ions

Question 33

When the depolarization near the axon hillock reaches about ___ as a result of summation of EPSPs, a neuron will fire an action potential

Answer 33

−55 mv

Question 34

is a summation of signals that brings the membrane closer to the threshold (depolarizing effect)

Answer 34

excitatory postsynaptic potential (EPSP)

Question 35

drives the membrane away from threshold by a hyperpolarizing effect.

Answer 35

inhibitory postsynaptic potential (IPSP)

Question 36

a temporary increase in postsynaptic membrane potential within dendrites or cell bodies caused by the flow of sodium ions into the postsynaptic cell

Answer 36

excitatory postsynaptic potential (EPSP)

Question 37

they hyperpolarize the postsynaptic membrane and produce IPSP

Answer 37

GABA and glycine

Question 38

The most common inhibitory neurotransmitters in the nervous system are

Answer 38

γ-aminobutyric acid (GABA) and glycine

Question 39

is used at the great majority of fast excitatory synapses in the brain and spinal cord

Answer 39

Glutamate

Question 40

Glutamatergic neurons are particularly prominent in the ___

Answer 40

cerebral cortex.

Question 41

EPSP-producing glutamate receptors (4)

Answer 41

1. NMDA receptors (named for N-methyl-D-aspartate) 2. AMPA receptors (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate) 3. Kainate receptors 4. Receptors which are activated by quisqualate

Question 42

very important for controlling developmental synaptic plasticity and learning and memory function

Answer 42

NMDA receptor

Question 43

The function of NMDA receptors is totally dependent upon ___

Answer 43

AMPA receptors

Question 44

Kainate receptors can be activated by ___ and __

Answer 44

kainite and glutamate

Question 45

the most ubiquitous inhibitory neurotransmitter in the brain

Answer 45

GABA

Question 46

It was the first amino acid to be established as a neurotransmitter in vertebrate and invertebrate nervous systems

Answer 46

GABA

Question 47

GABA exerts its effects via ___ and ___ receptors

Answer 47

ionotropic (GABAA) metabotropic (GABAB)

Question 48

GABA A receptors are ___ channels that in response to GABA binding increases chloride influx into the neuron

Answer 48

chloride

Question 49

The GABA B receptors are ___ channels that when activated by GABA leads to potassium efflux from the cell

Answer 49

potassium

Question 50

the simplest of amino acids, consisting of an amino group and a carboxyl (acidic) group attached to a carbon atom.

Answer 50

Glycine

Question 51

a potent neurotransmitter in the spinal cord and brain

Answer 51

Glycine

Question 52

Glycine is a constituent of ___, an antioxidant tripeptide found in high concentrations in intestinal epithelial cells.

Answer 52

glutathione

Question 53

functions as an excitatory transmitter during embryonic development and is an essential coagonist at glutamatergic synapses containing the NMDA subtype of glutamate receptors.

Answer 53

Glycine

Question 54

____ converts the amino acid serine to glycine

Answer 54

Hydroxymethyl transferase

Question 55

Glycine receptors are ligand-gated ___ that increase Cl− influx.

Answer 55

ion channels

Question 56

Glycine molecules may be taken back into the presynaptic cell by two high affinity glycine transporters

Answer 56

Glyt-1 and Glyt-2

Question 57

Glyt-1 is found primarily in __ cells, whereas Glty-2 is found primarily in ___ cells

Answer 57

glial neuronal

Question 58

is a glycine antagonist which can bind to the glycine receptor without opening the chloride ion channel

Answer 58

Strychnine

Question 59

is a strychnine-sensitive glycoprotein which is composed of five subunit

Answer 59

GlyR

Question 60

are nonessential amino acids that do not cross the blood-brain barrier and, therefore, are synthesized from glucose and a variety of other precursors

Answer 60

Glutamate and aspartate

Question 61

The synthetic and metabolic enzymes for glutamate and aspartate have been localized to the two main compartments of the brain

Answer 61

neurons and glial cells

Question 62

the most abundant excitatory neurotransmitter in the CNS

Answer 62

Aspartate

Question 63

Unlike glycine, however, aspartate is an ___ neurotransmitter, which increases the likelihood of depolarization in the postsynaptic membrane

Answer 63

excitatory