Question 1

Some nerve fibers of the peripheral nervous system have the ability to regenerate after damage has occurred. Which of the following cells is most responsible for aiding in this regulation?
A) Schwann cells
B) astrocytes
C) oligodendrocytes
D) satellite cells

Accepted Answer

Schwann cells play a critical role in the regeneration of damaged nerve fibers in the peripheral nervous system. They assist in guiding the regrowing axons and provide a supportive environment for their regrowth. Astrocytes and oligodendrocytes are cells found in the central nervous system and are not directly involved in peripheral nerve regeneration. Satellite cells, found in muscle tissue, aid in muscle repair and regeneration, but not in nerve regeneration.

Question 2

Cell bodies of sensory neurons may be located in ganglia lying outside the central nervous system.

Accepted Answer

Sensory neurons can have their cell bodies located in ganglia outside the central nervous system, such as the dorsal root ganglia in the spinal cord.

Question 3

The action potential is caused by permeability changes in the plasma membrane.

Accepted Answer

The action potential is caused by changes in the permeability of ion channels in the plasma membrane, specifically the opening and closing of voltage-gated channels that allow ions to flow into or out of the cell, triggering a chain reaction of depolarization and repolarization.

Question 4

It is important for newly developed neurons to form synapses with other neurons. Which cells are most responsible for guiding the formation of these particular junctions?
A) microglial cells
B) Schwann cells
C) satellite cells
D) astrocytes

Accepted Answer

Astrocytes are known to play a crucial role in guiding the formation of synapses between neurons. They release chemical signals and provide physical support for the developing neurons to grow and form connections with neighboring cells. Microglial cells are immune cells that survey the brain for damage or infection, while Schwann cells and satellite cells are involved in support and maintenance of the peripheral nervous system.

Question 5

Nerve impulses leading to the brain carry information about cool temperatures on the skin. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
A) sensory (afferent) division
B) somatic nervous system
C) sympathetic division
D) parasympathetic division

Accepted Answer

The sensory (afferent) division of the nervous system is responsible for carrying sensory information from the body to the brain. This includes information about temperature, which is detected by thermoreceptors in the skin. Therefore, the nerve fibers sending signals about cool temperatures on the skin would belong to the sensory (afferent) division of the nervous system.

Question 6

Meningitis can be caused by infection of the central nervous system by bacteria. Which cells would be most responsible for removing the infection?
A) microglia
B) satellite cells
C) oligodendrocytes
D) Schwann cells

Accepted Answer

Microglia are the resident immune cells in the central nervous system and are responsible for removing pathogens and infected cells.

Question 7

Strong stimuli cause the amplitude of action potentials generated to increase.

Accepted Answer

The amplitude of action potentials does not vary with the strength of the stimulus; rather, it is the frequency of action potentials that increases with stronger stimuli.

Question 8

A stimulus traveling toward a synapse appears to open calcium ion channels at the presynaptic end, which in turn promotes fusion of synaptic vesicles to the axonal membrane.

Accepted Answer

This statement is true. When a stimulus arrives at a synapse, it triggers the opening of calcium ion channels on the presynaptic membrane. The influx of calcium ions promotes the fusion of synaptic vesicles with the membrane, causing the release of neurotransmitters into the synapse.

Question 9

During depolarization, the inside of the neuron's membrane becomes less negative.

Accepted Answer

During depolarization, the influx of positive ions causes the inside of the neuron's membrane to become less negative, leading to the potential difference across the membrane decreasing or becoming less negative.

Question 10

Cranial nerve II, the optic nerve sends nerve impulses to the brain carrying information about the things we see. These nerve fibers most likely belong to which division of the nervous system?
A) sensory (afferent) division
B) somatic nervous system
C) sympathetic division
D) parasympathetic division

Accepted Answer

The optic nerve is responsible for carrying visual information from the eyes to the brain, making it a sensory (afferent) nerve. Therefore, the nerve fibers sending this information belong to the sensory (afferent) division of the nervous system. The somatic nervous system refers to the division responsible for voluntary skeletal muscle movement, while the sympathetic and parasympathetic divisions are part of the autonomic nervous system, which regulates involuntary functions. None of these divisions are directly involved in the transmission of visual information.

Question 11

The peripheral nervous system is divided into afferent and efferent divisions.

Accepted Answer

The peripheral nervous system is indeed divided into afferent (sensory) and efferent (motor) divisions. Afferent neurons carry sensory information from the body to the central nervous system, while efferent neurons carry motor commands from the central nervous system to the muscles and organs.

Question 12

Axon diameter and degree of myelination determine nerve impulse conduction velocity.

Accepted Answer

Axon diameter and degree of myelination both have a significant impact on the speed of nerve impulse conduction. Larger axon diameter and greater myelination result in faster conduction speeds.

Question 13

In myelinated axons the voltage-regulated sodium channels are concentrated at the nodes of Ranvier.

Accepted Answer

In myelinated axons, the voltage-regulated sodium channels are clustered at the nodes of Ranvier, which are the small gaps between the myelin sheaths. This allows for saltatory conduction, where the action potential jumps between nodes and speeds up the conduction of the nerve impulse.

Question 14

Enkephalins and endorphins are peptides that act like morphine.

Accepted Answer

Enkephalins and endorphins are natural analgesics that act on the same receptors as morphine, producing pain relief and a feeling of well-being.

Question 15

Nerve impulses leading to the skeletal muscle carry information to direct movement. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
A) sensory (afferent) division
B) somatic nervous system
C) sympathetic division
D) parasympathetic division

Accepted Answer

The somatic nervous system is responsible for the voluntary control of skeletal muscles, so nerve impulses leading to skeletal muscle movement would be carried by nerve fibers from this division of the nervous system. The sensory division (A) is responsible for carrying sensory information to the central nervous system, while the sympathetic (C) and parasympathetic (D) divisions are responsible for involuntary control of organ systems.

Question 16

The concentration of ions in the chemical environment surrounding the neurons must be tightly regulated for neurons to function properly. Which of the following cells is most responsible for this?
A) astrocytes
B) satellite cells
C) Schwann cells
D) oligodendrocytes

Accepted Answer

Astrocytes are responsible for regulating the chemical environment surrounding neurons, including the concentration of ions. They do this by taking up excess ions and releasing them as needed. Satellite cells are found in peripheral ganglia and support neurons, but do not play a role in ion regulation. Schwann cells and oligodendrocytes produce myelin around axons and do not have a direct role in regulating ion concentration.

Question 17

Unipolar neurons have axons structurally divided into peripheral and central processes.

Accepted Answer

Unipolar neurons have only one main process extending from the cell body, which then splits into a peripheral process and a central process. The peripheral process carries information from sensory receptors towards the cell body, while the central process carries information away from the cell body towards the central nervous system.

Question 18

Reflexes are rapid, automatic responses to stimuli that will produce the same effect every time.

Accepted Answer

This is the definition of a reflex. When a specific stimulus is detected, a reflex response is triggered automatically and the response will be the same each time.

Question 19

A postsynaptic potential is a graded potential that is the result of a neurotransmitter released into the synapse between two neurons.

Accepted Answer

This statement accurately describes what a postsynaptic potential is.

Question 20

Nerve impulses are sent to slow the heart's rate of contraction. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
A) sensory (afferent) division
B) somatic nervous system
C) sympathetic division
D) parasympathetic division

Accepted Answer

The parasympathetic division of the autonomic nervous system is responsible for slowing the heart rate through the release of acetylcholine.

Quiz 11: Fundamentals of the Nervous System and Nervous Tissue

Some nerve fibers of the peripheral nervous system have the ability to regenerate after damage has occurred. Which of the following cells is most responsible for aiding in this regulation?

Cell bodies of sensory neurons may be located in ganglia lying outside the central nervous system.

The action potential is caused by permeability changes in the plasma membrane.

It is important for newly developed neurons to form synapses with other neurons. Which cells are most responsible for guiding the formation of these particular junctions?

Nerve impulses leading to the brain carry information about cool temperatures on the skin. The nerve fibers sending these signals will most likely belong to which division of the nervous system?

Meningitis can be caused by infection of the central nervous system by bacteria. Which cells would be most responsible for removing the infection?