Question 1

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 nervous system is responsible for controlling the "rest and digest" responses in the body, which includes slowing the heart rate. Therefore, nerve fibers sending signals to slow the heart rate will most likely belong to the parasympathetic division of the nervous system.

Question 2

Neurons in the CNS are organized into functional groups.

Accepted Answer

Neurons in the CNS are organized into functional groups, including sensory neurons, motor neurons, and interneurons, that work together to process information, generate appropriate responses, and maintain homeostasis.

Question 3

Match the following:
-Involved in control of rhythmic activities such as breathing.
A)Parallel after-discharge circuit
B)Reverberating circuit
C)Diverging circuit
D)Converging circuit

Accepted Answer

The circuit involved in control of rhythmic activities such as breathing is a reverberating circuit, which is a type of circuit that continues to fire even after the initial stimulus has stopped. This allows for the sustained control of rhythmic activities like breathing.

Question 4

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

Accepted Answer

The action potential is caused by changes in ion permeability in the plasma membrane of a neuron. Specifically, when a neuron receives a stimulus, voltage-gated ion channels open and allow an influx of Na+ ions into the cell, causing depolarization and initiating an action potential. This is followed by the opening of voltage-gated K+ channels, allowing an efflux of K+ ions and repolarizing the cell. Thus, changes in permeability are critical for the generation of an action potential.

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 sending sensory information from sensory receptors to the central nervous system, including information about temperature on the skin. The somatic nervous system is responsible for voluntary movements, and the sympathetic and parasympathetic divisions are part of the autonomic nervous system and are involved in the regulation of various involuntary processes such as heart rate and digestion.

Question 6

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 7

The all-or-none phenomenon as applied to nerve conduction states that the whole nerve cell must be stimulated for conduction to take place.

Accepted Answer

The all-or-none phenomenon refers to the principle that once a nerve impulse is initiated, it will travel along the neuron all the way to the end without decreasing in strength, but it does not require the whole nerve cell to be stimulated for conduction to take place; rather, it requires reaching a certain threshold of stimulation at the trigger zone.

Question 8

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 is true.

Question 9

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

Accepted Answer

Ganglia are clusters of nerve cell bodies located outside the central nervous system. In the case of sensory neurons, their cell bodies may be located in ganglia found nearby the spinal cord or peripheral nervous system.

Question 10

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 is a correct statement about the process of synaptic transmission. When a stimulus reaches the presynaptic terminal, it triggers the opening of calcium ion channels, causing an influx of calcium ions. This increase in calcium concentration then promotes the fusion of synaptic vesicles with the axonal membrane, releasing neurotransmitters into the synaptic cleft.

Question 11

Match the following:
-Different types of sensory input can have the same ultimate effect.
A)Parallel after-discharge circuit
B)Reverberating circuit
C)Diverging circuit
D)Converging circuit

Accepted Answer

A converging circuit is when multiple sources of sensory input converge onto a single neuron. This can result in the same ultimate effect, such as the sensation of pain from different types of stimuli (e.g. heat, pressure, chemicals).

Question 12

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 voluntary movement and skeletal muscle control, so the nerve fibers responsible for directing movement would belong to this division. The sensory (afferent) division carries information from sensory receptors to the central nervous system, while the sympathetic and parasympathetic divisions are involved in involuntary functions such as organ regulation and the fight or flight response.

Question 13

Enkephalins and endorphins are peptides that act like morphine.

Accepted Answer

Enkephalins and endorphins are opioid peptides that bind to the same receptors in the brain as morphine, producing analgesic effects and feelings of euphoria.

Question 14

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

Accepted Answer

Voltage-regulated sodium channels are necessary for action potential generation and propagation. They are concentrated at the nodes of Ranvier in myelinated axons, which are the small unmyelinated gaps along the axon that allow for the regeneration of the action potential.

Question 15

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

Accepted Answer

This is a definition of reflexes and is therefore true.

Question 16

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

Accepted Answer

Axon diameter and the degree of myelination are two major factors that determine the speed at which nerve impulses travel along a neuron. A larger axon diameter results in faster conduction of nerve impulses, while myelination insulates the axon and further increases the speed of impulse transmission.

Question 17

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

Accepted Answer

Unipolar neurons have a single short process leaving the cell body that quickly branches into two fibres, a peripheral process and a central process.

Question 18

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 carries sensory information from the eye to the brain. Therefore, the nerve fibers belong to the sensory (afferent) division of the nervous system, which is responsible for transmitting sensory information from the body to the central nervous system. The somatic nervous system controls voluntary movements and the sympathetic and parasympathetic divisions are both part of the autonomic nervous system, which controls involuntary processes in the body.

Question 19

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

Accepted Answer

During depolarization, the voltage-gated ion channels open and allow positively charged ions, such as sodium (Na+) and calcium (Ca2+), to enter the neuron, which makes the inside of the neuron's membrane less negative. This leads to the generation of an action potential.

Question 20

Match the following:
-Involved in activating fibers of a skeletal muscle such as the biceps muscle.
A)Parallel after-discharge circuit
B)Reverberating circuit
C)Diverging circuit
D)Converging circuit

Accepted Answer

Diverging circuits are used in the nervous system to spread a signal from one neuron to multiple neurons, which is necessary for activating multiple muscle fibers in a skeletal muscle like the biceps.

Quiz 11: Fundamentals of the Nervous System and Nervous Tissue

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?

Neurons in the CNS are organized into functional groups.

Match the following: -Involved in control of rhythmic activities such as breathing.