Question 1

When two or more presynaptic neurons synapse with a single postsynaptic neuron in the CNS,a(n)_______ pathway is formed.

Accepted Answer

A) convergent 
B) divergent 
C) reverberating 
D) somatic 
E) sensory

Question 2

Which of the following is NOT true of reactive astrocytosis?

Accepted Answer

A) injury site is blocked off 
B) scars limit regeneration 
C) causes the spread of inflammation 
D) reduces injury to surrounding tissue

Question 3

Which of the following statements regarding neuroglia is false?

Accepted Answer

A) Neuroglia serve as the major supporting tissue in the CNS. 
B) Neuroglia form part of the blood-brain barrier. 
C) Neuroglia produce action potentials for skeletal muscles. 
D) Neuroglia form myelin sheaths around some axons. 
E) Neuroglia produce cerebrospinal fluid.

Question 4

An action potential

Accepted Answer

A) occurs when the local potential reaches threshold level. 
B) propagates across the plasma membrane in a decremental fashion. 
C) has no repolarization phase. 
D) is an example of negative feedback. 
E) cannot transmit information.

Question 5

Voltage-gated sodium channels are sensitive to changes in the extracellular concentration of

Accepted Answer

A) potassium ions. 
B) proteins. 
C) sodium ions. 
D) chloride ions. 
E) calcium ions.

Question 6

Which of the following is true?

Accepted Answer

A) Unmyelinated axons rest in invaginations of Schwann cells or oligodendrocytes.. 
B) Myelination will not influence the speed of conduction of action potentials. 
C) The myelin sheath inhibits the flow of electrical charges at nodes. 
D) The myelin sheath is a protein wrapping. 
E) The myelin sheath does not electrically insulate the axons from one another.

Question 7

A series of local potentials causes the membrane potential to move to -80 mV.Predict the result.

Accepted Answer

A)  threshold is reached 
B)  depolarization occurs 
C)  the neuron is hyperpolarized 
D)  information of frequency is needed to predict the result 
E)  the neuron releases neurotransmitter in response

Question 8

-Identify structure "C" on the neuron.

Accepted Answer

A) Schwann cell 
B) Node of Ranvier 
C) neuron cell body (soma) 
D) dendrites 
E) axon

Question 9

Viagra is used to treat erectile dysfunction by prolonging the effects of _____ on blood vessels.

Accepted Answer

A) substance P 
B) dopamine 
C) GABA 
D) nitric oxide (NO)

Question 10

In hyperpolarization

Accepted Answer

A) K+ ions tend to diffuse out of the cell. 
B) the plasma membrane's permeability to K+ decreases. 
C) the resting membrane potential moves closer to zero. 
D) Na+ ions enter the cell in large numbers. 
E) the resting membrane potential becomes more positive.

Question 11

Low levels of ___ can have dire consequences on the functioning of neurons because of its role in membrane repolarization.

Accepted Answer

A)  sodium ions 
B)  potassium ions 
C)  chloride ions 
D)  hydrogen ions

Question 12

The central nervous system

Accepted Answer

A) is the site for processing information. 
B) initiates visual and auditory stimuli. 
C) consists of 43 pairs of nerves. 
D) is totally involuntary. 
E) does not interact with the peripheral nervous system.

Question 13

The absolute refractory period assures

Accepted Answer

A) prolonged depolarization during the action potential. 
B) completion of repolarization before another action potential. 
C) that no after-potential occurs. 
D) reversal of the direction of propagation of the action potential. 
E) that the stimulus is strong enough to elicit a response.

Question 14

Match the neuroglial cell with its function.
-astrocytes

Accepted Answer

A) influence function of blood-brain barrier 
B) macrophages in CNS 
C) produce cerebrospinal fluid 
D) form myelin sheath around axons in CNS 
E) form myelin sheath around part of the axon in the PNS

Question 15

Neurotransmitter is being released at a synapse.Which of the following occurs last?

Accepted Answer

A) Calcium ions enter the presynaptic terminal. 
B) Synaptic vesicles release neurotransmitter by exocytosis. 
C) An action potential is produced in the postsynaptic membrane. 
D) Neurotransmitter flows rapidly across the synaptic cleft. 
E) Neurotransmitter binds with the receptor on the postsynaptic membrane.

Question 16

Cerebrospinal fluid is produced by ____________ cells.

Accepted Answer

The answer of Cerebrospinal fluid is produced by ____________ cells....

Question 17

If the ECF around a nerve cell is replaced with an isotonic saline solution that contains potassium ions and other solutes at concentrations very close to the ECF concentrations of a normal cell,the result is

Accepted Answer

A) no resting membrane potential. 
B) hyperpolarized membrane. 
C) depolarized membrane. 
D) a resting membrane potential close to its normal value. 
E) None of these choices is correct.

Question 18

____________ are neuroglia cells that are macrophages.

Accepted Answer

The answer of ____________ are neuroglia cells that are macrophages....

Question 19

An inhibitory postsynaptic potential (IPSP)can result from the

Accepted Answer

A) influx of calcium ions. 
B) influx of sodium ions. 
C) influx of chloride. 
D) outflow of potassium ions. 
E) either influx of chloride or outflow of potassium ions.

Question 20

____________ are collections of neuron cell bodies located outside of the central nervous system.

Accepted Answer

The answer of ____________ are collections of neuron cell bodies...

Exam 11: Functional Organization of Nervous Tissue

When two or more presynaptic neurons synapse with a single postsynaptic neuron in the CNS,a(n) _______ pathway is formed.