Midterm 1 neurobiology

Which of these glial cells are most abundant

A: astrocytes

B. Oligodendrocytes

C. Myelinating glia

D. Micro glia

astrocytes

What is the role of mircroglia in the nervous system?

A. Structural support

B. Insulation of axons

C.cleaning up debris at injury sites

D. Carrying electrical signals

cleaning up debris at injury sites

what is the main function of ion channels in nerve cell membranes?

A. To produce myelin sheath

B. To faciliate the flow of ions across the membrane

C. To insulate the cell

D. To provide structural support to the cell

to faciliate the flow of ions across thee membrane

the equilibrium potential Eeq is the potential at which the electrical and the chemical driving forces are equal and opposite so there is positive current flow

True

False

false

by using GHK equations we can determine that resting membrane potential is dominated by ion with high conductance

True

False

true

What does brain bow technique visualize

A. Blood flow in the brain

B. Electrical activity of the brain

C. Different types of neuron in various colors

D. The chemical environment inside neurons

Different types of neurons in various colors

How does the resting membrane potential remain stable.

A. Through high sodium premeability

B. Through equal selective permeability for all ions

C. Through selective permeability and active transporters

D. Through constant action potentials

Through selective permeability and active transporters

Which method is used for studying large scale brain anatomy

A. Optogenetics

B. PCR analysis

C. MRI

D. Electrophoresis

MRI

Which statement best desribes the function of dendrites

A. They generate electrical signals

B. They receive and integrate signals from other neurons

C. They propagate action potentials

D. They release neurotransmitters

They receive and integrate signals from other neurons

What does the term absolute refractory period refer to

A. The period when the neuron cannot fire another action potential

B. The time when only graded potentials can occur

C. A phase when the cell is only postitvely charged

D. The interval for potassium ions rebalancing

The period when the neurons cannot fire another action potential

How does the voltage clamp method contribute to our understanding of ion channels

A. By changing the membrane potential constantly

B. By keeping the membrane potential constant while measuring currents

C. By allowing unlimited iron flow

D. By closing all ion channels

By keeping the membrane potential constant while measuring currents

What does an IV curve illustrate

A. The size of the axon hillock

B. The action potential duration

C. The ion concentration across a membrane

D. The relationship between voltage and current in an electrical circuit

The relationship between voltage and current in an electrical circuit

What causes the inactivation of Na+ channels during an action potential

A. A decrease in membrane capaciatance

B. A mechanical block by a part of the channel protein

C. Permanent closure of the channel

D. Hyper polarization of the membrane

A mechanical block by a part of the channel protein

The patch clamp technique allow scientist to study individual ion channels and their properties

A. True

B. False

True

How do voltage-gated Na+ channels contribute to the rising phase of the action potential

A. By closing and stopping the current

B. By allowing an influx of Na+ ions which depolarizes the membrane

C. By pumping Na+ ions out of the cell

D. By decreasing the membrane resistance

By allowing an influx of Na+ ions which depolarizes the membrane

What causes ion selectivity in channels

A. The electrical resistances of the neurons

B. The specific pore size and charged residues along the pore

C. The amount of myelin around the axon

D. The length of the axon hillock

The specific pore size and charged residues along the pore

Smaller value of T allows action potential to propagate quickly

True

False

True

In normal neurons, K+ flows down concentration gradient out of cell, and Na+ flows

True

False

True

Which of these are NOT true for Antiporters

A. It exchanges ions across the membrane

B. Using antiporters two ions move in opposite directions

C. Using antiporters two ions move in same direction

D. Transports two dissimilar ions

Using antiporters two move in same direction

What is the main difference between electrical and chemical synapses

A. Electrical synapses are so lower than chemical synapses

B. Chemical synapses allow modulation and amplification

C. Electrical synapses use neurotransmitters

D. Chemical synapses directly pass current between cells

chemical synapses allow modulation and amplification

What function do gap junctions serve at electrical synapses

A. Amplify signals

B. Allow diffusion of small molecules between cells

C. Block neurotransmitter release

D. Increase the synaptic delay

Allow diffusion of small molecules between cells

How does Ca 2+ influence neurotransmitter release at synapses

A. It decreases neurotransmitter release

B. It is necessary for neurotransmitter release

C. It had no effect on neurotransmitter release

D. It only affects receptors sensitivity

It is necessary for neurotransmitter release

Synptotagmin is part of the docking protein complex

A True

B False

False

How does Botuliunmum toxin affect neurotransmitters release

A. It promotes neurotransmitters release

B. It blocks the release by. Cleaving docking proteins

C. It increases the number of active receptor

D. It has no effect on neurotransmitter

It blocks the release by cleaving docking proteins

How are GABA A and GABA B different? Mention one structural and one functional difference

Structural - GABA A is ionotropic and GABA B is metabotropic

Functional - both cause inhibition, GABA A (opens ion channels) GABA B (uses messenger pathways)

What are two tupes of neurotransmitter receptors

A. Ionotrpic and metabotropic

B. Electrical and chemical

C. Active and Passive

D. Fast and slow

ionotropic and metabotropic

Excitatory EPSP takes place if the reversal potential is more positive than the threshold

True

False

True

Arrange these into the right order: 1. Receptor Binding 2. Ion channels open/close 3. Neurotransmitter release 4. Postsynaptic cell inhibited/ excited 5. Change in postsynaptic postsynpatic potential 6. Conductance change causes current flow

3. Neurotransmitter Release

1. Receptor binding

2. Ion channels open/close

6. Conductance change causes current flow

5. Change in postsynaptic potential

4. Postsynaptic cell inhibited/excited

Glutamate is most widespread excitatory neurotransmitter

True

False

True

What effect does cocaine have on neurotransmitter reuptake

A. Enhances the reuptake of serotonin

B. Blocks the reuptake of norepinephrine

C. Increases the breakdown of neurotransmitters

D. None of the above

blocks the reuptake of norepinephrine

What unique feature characterizes the NMDA receptor

A. Dependence or serotonin

B. Activation by dopamine only

C. Activation by dopamine only

D. Lacks of a ligand binding site

Voltage-dependence and magnesium block

Which neurotransmitter was thought to be asssociated with runners high

A. Dopamine

B. Endorphins

C. Endocannabinoids

D. Serotonin

endorphins

Kinases remove phosphate groups and phosphates add them

True

False

false

Which of the following is wrong about CREB

A. CREB stands for cAMP-responses element binding

B. It is a protein

C. It is a part of the DNA

D. It regulates transcription

It is a part of DNA

Which of these creates the effect of happiness

A. GABA

B. Acetylcholine

C. Dopamine

D. NMDA

dopamine

In the sequence of events in neurotransmission, which event occurs just after the action potential arrives at the presynaptic terminal

A. Packing of the neurotransmitter

B. Delivery of the neurotransmitter to the presynaptic terminal

C.fusion of the synaptic vesticles with the presynaptic membrane

D. Influx of Ca+ into the presynaptic terminal

E. Release of the neurotransmitter

influx of Ca+ into the presynaptic membrane

Which statements about EPSP in the central nervous system is true

A. They are much larger than end plate potentials

B. The instance between inputs does not affect the ability of EPSPs to summate

C. The time between inputs does not affect the ability to EPSPs to summate

D. Their effect in the central nervous system can be nullified by IPSPs

E. They can be hyper polarizing

their effect in the central nervous system can be nullified by IPSP

By which proposed molecular mechanisms does Ca+ promote fusion of synaptic vesicles

A. By binding to synapsin

B. By binding SNARE proteins to the complex formation

C. By binding to SNARE proteins after the complex formation

D. By binding tp synaptotagmin and promoting formation of the SNARE complex which facilitates fusion

E. By binding to and inducing changes in synaptotagmin that causes the plasma to curve, facilitating fusion

by binding to and inducing changes in synaptotagmin that causes the plasma membrane to curve, facilitating fusion

How would application of a Ca+ channel blocker affect the function of a synapse

A. It would increase the magnitude of postsynpatic potential

B. It would decrease the magnitude of postsynaptic potential

C. It would elimate the postsynaptic potential but have no effect on presynaptic neuron

D. It would elimate the postsynaptic potential and the presynaptic Ca+ current

It would elimate the postsynaptic potential and the presynaptic Ca+

The acetylcholine receptor at the neuromuscular junction would best be described as

A. Channel-linked receptor

B. Enzyme-linked receptor

C. G-protein-coupled receptor

D. Nuclear receptor

Channel -linked receptor

Which of the following does not contribute to maintaining low levels of Calcium, in resting nerve cells

A. Voltage-gated calcium channels

B. The plasma membrane calciu ATPase

C. The smooth endoplasmic reticulum calcium ATPase

D. Mitochondria

voltage-gated calcium channels

What is the immediate consequences of Mg+ blockade removal from the NMDA receptors

A: postsynpatic EPSP

B: Cat2+ influx into the presynaptic terminal

C. Cat2+ influx into the postsynaptic terminal

D. Glutamate binding to its receptors

Ca2+ influx into te postsynaptic terminal