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Flashcards in MCQs Deck (72):
1

Gray’s Type 1 synapses are ___________ while Gray’s Type 2 synapses are____________.

asymmetric; symmetric

2



The action potential depends on the presence of extracellular ___________.


sodium

3

Antagonists of which receptor are used as antiemetics, anxiolytics, and antipsychotics?

5HT3

4



_________ is actively concentrated inside the cell and __________ outside.

Potassium in, Sodium and Calcium out

5



________________ is/are an example of a catecholamine neurotransmitter.

DA, NE, Epi

6

In general, which segment of a GPCR is responsible for specificity of the receptor?

3rd intracellular loop

7



The neurons of the substantia nigra are ____________ and contain the pigment ___________.

dopaminergic; neuromelanin

8


_____________ is the major excitatory transmitter in the brain and __________ is the major inhibitory transmitter.

Glutamate and GABA

9

Hodgkin and Huxley found that the resting membrane potential of the inside versus the outside of the axon is ___________.

-60mV

10



Endocannabinoids are ___________________.

hydrophobic, retrograde messengers,
found on both GABA and Glutamate nerve endings

11

What is Neurotensin?

Peptide neurotransmitter that requires calcium to be released.

12



Muscarinic ACh receptors are both _____

Presynaptic and postsynaptic

13

In mammals, at membrane potentials negative to –102 mV, K+ ions tend to flow ____ the cell; increasing the membrane conductance to K+ causes the membrane potential to become more ___________.

in; depolarized

14



Calcium currents ______________.

contribute to electrophysiological processes.

are important for 2nd messenger systems

voltage sensitive

15



________________ is involved in the enzymatic degradation of catecholamines.

MAO

16

Of the types of neuroglia, ___________ play a role in nerve growth while ___________ serve immune functions for neurons in the brain.

Astrocytes, microglia

17

The blood-brain barrier is formed by the encapsulation of ____________ by ___________ which creates selective permeation into the brain tissue.

capillaries; neuroglia

18

Purinergic receptors are ________ that bind ATP and __________.

GPCRs; adenosine

19

Which of these ions are permeated through 5HT3 ionotropic receptors?

Na+, K+

20



The basic structure of a neuron includes a cell body, a variable number of __________, and a single _________.

dendrites; axon

21

In the periphery, ______________ are the primary immune support for neurons.

Schwann Cells

22

Cystic fibrosis is caused by a mutation of a ____________ channel.

Chloride

23



Which part of a neuron is responsible for generating action potential?

axon hillock

24



Which of the following are important for the Nernst equation?

temperature, ionic concentration outside and inside the cell.

25



Myelin is synthesized in the periphery by _____________ and in the CNS by ___________.

Schwann cells; oligodendrocytes

26

The GABAA receptor is ____________ and is selective for __________.

ionotropic; anions

27

The rate of acetylcholine synthesis is determined by ______________.

choline

28

Tetraethylammonium (TEA) selectively blocks voltage-dependent _______ currents.

Potassium

29

Curare works by binding to the postsynaptic receptor for which neurotransmitter?

acetylcholine

30



In general, GPCRs are comprised of ____________ polypeptide (s) and spans the membrane ________ times.

single, 7

31

The active zone of a presynaptic neuron contains numerous ______________, and the membrane of this area is densely packed with ______________.

synaptic vesicles; calcium channels

32

Norepinephrine is converted to epinephrine by ________________.

Phenylethanolamine N-Methyltransferase

33

The nicotinic receptor, GABAA receptor, and the 5HT3 receptor are all

ionotropic

34

Protein zero is the primary building block of

peripheral myelin.

35

Vesicular monoamine transporters are inhibited by _______________.

Reserpine

36



The ____________ determines the quantity and connections that a neuron makes.

dendritic tree

37

NOS is activated by ________________.

Ca++ binding to calmodulin

38



The capillary endothelial cells in the brain contribute to the blood-brain barrier through use of

tight junctions

39

The ____________ refers to the membrane potential following an action potential that typically becomes more negative than the original value.

after hyper-polarization

40

Which enzyme that catalyzes monoamine synthesis is found in dopamine neurons?

monoamine oxidase

41



GABAergic interneurons of the cerebellar and cerebral cortex are fall into which category of neurons?

inhibitory with local contacts

42

Which of these is a connection between populations of neurons projecting from one brain region to another?

macrocircuit

43

The synaptic cleft is bounded on one side by the presynaptic ____________ and the other with the postsynaptic _________.

terminal bouton; dendrites

44



Muscarinic ACh and beta adrenergic receptors are

GPCRs.

45

Action potentials are produced through an increase in ________ conductance followed by an increase in ________ conductance.

Sodium, potassium

46

Low threshold calcium currents have a threshold of ________ mV.

- 65

47

Neurons that spontaneously generate action potentials at low frequencies (1-10 Hz) are associated with ____________.

ACh

48



NMDA receptors require which of these in order to open their channels?

glutamate binding and depolarization

49



The nicotinic receptor is selectively permeable to ___________ due to its structure creating a _________ charged pore.

cations, negatively

50

The brain accounts for _______ percent of the total serotonin found in the body.

1

51

The membrane potential where there is no net flow of ions is known as ____________.

equilibrium potential

52

The voltage-sensitive K+ current that regulates the responsiveness of the neuron to depolarizing inputs is known as the _____ current.

m

53

D1-like receptors _________ adenylate cyclase and D2-like receptors _________ adenylate cyclase.

activate, inhibit

54

Prozac works by blocking _____________.

DAT and SERT

55

Neuropeptide receptors are

GPCRs

56

When a GPCR is activated, it couples to a _____________ initiating the exchange of ______________.

G-protein; GDP for GTP

57

Dopamine is converted to norepinephrine by ________________.

Dopamine 3-Hydroxylase

58

Catacholamines are release peripherally by___________________.

Tyramine

59

Calcium ion permeability of neuronal nicotinic receptors is__________ compared to muscle nicotinic receptors?

higher

60

Tetrodotoxin (TTX) selectively blocks voltage-dependent _______ currents.

sodium

61

High threshold calcium channels have ____ homologous domains, each with ____ regions.

four; six

62

Which of these are excitatory projection neurons?

pyramidal cells

63

A single GPCR can activate _______ G-protein (s).

many

64

Acetycholinesterase is responsible for the____________ of acetylcholine.

inactivation

65

Which of these is a local inhibitory interneuron of the cerebral cortex?

basket cell, double bouquet, chandelier cell

66

Action potential transmission in myelinated neurons propagates very rapidly due to its ability to ‘leap’ down the axon on the ___________ that occur between ___________.

Nodes of Ranvier; myelin internodes

67

Glycine receptors are __________ located in the spinal cord and brain stem and are selectively permeable to _________.

inhibitory; calcium ions

68

Nicotinic receptors open in response to the binding of _____ acetylcholine molecules that produces a conformational change in the _______ subunit.

two; TM2

69

Desensitization of GPCRs occurs when PKA or PKC _________ sites on the _______ intracellular loop.

phosphorylates; third

70

High-affinity neuronal reuptake of neurotransmitters requires ______.

Na+ K+ Cl-

71

The absolute refractory period is mediated by the inactivation of ____channels.

Na+

72

At normal resting membrane potential, NMDA receptors are blocked by

Mg