Question 1

In an axodendritic synapse, the region of the postsynaptic neuron that binds the released neurotransmitter is the
A) synapse.
B) axon terminal.
C) axon.
D) cell body.
E) dendrite.

Accepted Answer

In an axodendritic synapse, the axon terminal of the presynaptic neuron releases neurotransmitters which bind to receptors located on the dendrites of the postsynaptic neuron. Therefore, the region of the postsynaptic neuron that binds the released neurotransmitter is the dendrite.

Question 2

This part of the neuron may have branching collaterals.
A) synapse
B) axon terminal
C) axon
D) cell body
E) dendrite

Accepted Answer

Axons can have branching collaterals that allow a single neuron to send signals to multiple target neurons, spreading the signal to different parts of the nervous system.

Question 3

Which of the following statements concerning sensory neurons is incorrect?
A) Most are pseudounipolar.
B) Most have their cell bodies in ganglia outside the CNS.
C) They have peripheral and central processes.
D) They contain only dendrites.

Accepted Answer

Sensory neurons contain both dendrites and an axon, which transmits the signal to the CNS.

Question 4

Mitochondria are particularly abundant here.
A) synapse
B) axon terminal
C) axon
D) cell body
E) dendrite

Accepted Answer

Mitochondria are necessary for providing energy for cellular functions, including neurotransmitter release at the axon terminal. Therefore, mitochondria are particularly abundant in the axon terminal.

Question 5

This tends to be the longest cytoplasmic projection from a neuron.
A) synapse
B) axon terminal
C) axon
D) cell body
E) dendrite

Accepted Answer

The axon is the longest cytoplasmic projection from a neuron.

Question 6

The majority of neurons in the body are
A) multipolar.
B) bipolar.
C) unipolar.
D) pseudounipolar.

Accepted Answer

The majority of neurons in the body are multipolar, which means they have several dendrites and one axon arising from the cell body. Bipolar neurons have one dendrite and one axon arising from opposite ends of the cell body, while unipolar neurons have one process coming off the cell body that divides into two branches, each ending in a sensory receptor. Pseudounipolar neurons have a single process that divides into two branches, one going to a sensory receptor and the other going to the central nervous system. While all of these types of neurons are present in the body, multipolar neurons are the most common.

Question 7

Most synapses transmit communicating signals using
A) chemical signaling molecules-neurotransmitters.
B) electrical impulses travelling through gap junctions.
C) physical contact between adjacent neurons.
D) chemical signaling molecules released from neuroglia.

Accepted Answer

The majority of synapses use chemical signaling molecules known as neurotransmitters to transmit signals between neurons. These molecules are released from the presynaptic neuron and bind to receptors on the postsynaptic neuron, causing a response.

Question 8

In this part of a neuron, neurofilaments, actin microfilaments, and microtubules are particularly abundant, providing structural support and a transport network.
A) synapse
B) axon terminal
C) axon
D) cell body
E) dendrite

Accepted Answer

The axon is the part of the neuron that is responsible for transmitting electrical impulses away from the cell body towards other neurons or target cells. It is in this part of the neuron that neurofilaments, actin microfilaments, and microtubules are particularly abundant, providing structural support and a transport network for molecules and organelles to move along the axon.

Question 9

Which of the following statements about neurotransmitters is false?
A) They alter the charge of the postsynaptic neuron membrane.
B) They are waves of positive charges that travel down axons.
C) They are released from synaptic vesicles.
D) They diffuse across the synaptic cleft.

Accepted Answer

Neurotransmitters are not waves of positive charges that travel down axons. They are chemical messengers that are released from the presynaptic neuron, diffuse across the synaptic cleft, and alter the charge of the postsynaptic neuron membrane.

Question 10

Action potentials travel along the
A) axon membrane.
B) dendrite membrane.
C) cell body.
D) myelin.

Accepted Answer

Action potentials are propagated along the axon membrane due to the presence of voltage-gated ion channels that allow for the rapid inflow and outflow of ions, resulting in a rapid depolarization and repolarization of the membrane potential. Dendrites and the cell body do not have voltage-gated ion channels and are not involved in the propagation of action potentials. Myelin is involved in the propagation of action potentials but does not actually conduct the electrical signal; instead, it helps to increase the speed of conduction by allowing the action potential to "jump" from one node of Ranvier to the next.

Question 11

This is the site of communication between neurons.
A) synapse
B) axon terminal
C) axon
D) cell body
E) dendrite

Accepted Answer

The synapse is the gap between two neurons where communication occurs through the release and uptake of neurotransmitters. The other options are parts of a neuron but not specifically where communication between neurons occurs.

Question 12

The chemical substance that is released at axon terminals is called a
A) hormone.
B) neurotransmitter.
C) synaptic vesicle.
D) Nissl body.

Accepted Answer

The chemical substance that is released at axon terminals is a neurotransmitter. Hormones are released by endocrine glands into the bloodstream, synaptic vesicles are the organelles in which neurotransmitters are stored, and Nissl bodies are clusters of rough endoplasmic reticulum found in the cell body of neurons.

Question 13

Which of the following statements about an axon is false?
A) It is also referred to as a nerve fiber.
B) It has branches.
C) It carries nerve impulses toward the cell body.
D) It has a uniform diameter.

Accepted Answer

Axons carry nerve impulses away from the cell body, not toward it.

Question 14

All of the following are characteristics of dendrites except that they
A) are more extensive branching than axons.
B) always conduct action potentials.
C) conduct signals toward the cell body.
D) typically occur as more than one per cell.

Accepted Answer

Dendrites do not conduct action potentials, as they lack the voltage-gated ion channels that are necessary for action potential generation. They instead generate graded potentials that may or may not reach the threshold for action potential firing in the cell body.

Question 15

Vesicles containing neurotransmitters are located in
A) a synaptic cleft.
B) axon terminals.
C) the postsynaptic region of dendrites.
D) the nodes of Ranvier.

Accepted Answer

Vesicles containing neurotransmitters are located in the axon terminals, which are the end points of axons that form connections with other cells, such as neurons or muscle cells. When an action potential reaches the axon terminal, it triggers the release of neurotransmitters from these vesicles into the synaptic cleft, the small space between the axon terminal and the target cell. Thus, option B is the correct choice. The other options are not correct because the synaptic cleft and postsynaptic region of dendrites are not locations for vesicles containing neurotransmitters, and the nodes of Ranvier are regions of myelinated axons that lack vesicles altogether.

Question 16

The ________ of a presynaptic neuron associates with the dendrite of a postsynaptic neuron.
A) synapse
B) axon terminal
C) axon
D) cell body
E) dendrite

Accepted Answer

The axon terminal of a presynaptic neuron is the part that associates with the dendrite of a postsynaptic neuron, forming a synapse where neurotransmitters are released to communicate between neurons.

Question 17

An axosomatic synapse occurs between the axon terminals of one neuron and the ________ of a proximal neuron.
A) synapse
B) axon terminal
C) axon
D) cell body
E) dendrite

Accepted Answer

An axosomatic synapse occurs between the axon terminals of one neuron and the cell body (soma) of a proximal neuron.

Question 18

This neuronal region transmits electrical impulses away from the cell body.
A) synapse
B) axon terminal
C) axon
D) cell body
E) dendrite

Accepted Answer

The axon is the part of the neuron that transmits electrical impulses away from the cell body.

Question 19

Which relatively rare type of neuron has two processes extending from opposite sides of the cell body?
A) bipolar
B) multipolar
C) pseudounipolar
D) unipolar

Accepted Answer

Bipolar neurons have two processes extending from opposite sides of the cell body, while unipolar neurons have a single process extending from the cell body, and multipolar neurons have multiple processes extending from the cell body. Pseudounipolar neurons have a single process that splits into two branches, but these branches are connected to the cell body by a short stem, rather than extending directly from the cell body itself. Therefore, the correct choice is A) bipolar.

Question 20

Which of the following is the correct path an impulse takes across a synapse?
A) axon of postsynaptic neuron, dendrite of presynaptic neuron, synaptic cleft
B) dendrite of presynaptic neuron, synaptic cleft, axon of postsynaptic neuron
C) axon of presynaptic neuron, synaptic cleft, dendrite of postsynaptic neuron
D) synaptic cleft, dendrite of postsynaptic neuron, axon of presynaptic neuron

Accepted Answer

The impulse travels from the axon of the presynaptic neuron, across the synaptic cleft, and to the dendrite of the postsynaptic neuron. This is the correct order of events for synaptic transmission.

Quiz 12: Fundamentals of the Nervous System and Nervous Tissue

In an axodendritic synapse, the region of the postsynaptic neuron that binds the released neurotransmitter is the

This part of the neuron may have branching collaterals.

Which of the following statements concerning sensory neurons is incorrect?

Mitochondria are particularly abundant here.

This tends to be the longest cytoplasmic projection from a neuron.

The majority of neurons in the body are

Most synapses transmit communicating signals using

In this part of a neuron, neurofilaments, actin microfilaments, and microtubules are particularly abundant, providing structural support and a transport network.

Which of the following statements about neurotransmitters is false?

Action potentials travel along the

This is the site of communication between neurons.

The chemical substance that is released at axon terminals is called a

Which of the following statements about an axon is false?

All of the following are characteristics of dendrites except that they

Vesicles containing neurotransmitters are located in

The ________ of a presynaptic neuron associates with the dendrite of a postsynaptic neuron.

An axosomatic synapse occurs between the axon terminals of one neuron and the ________ of a proximal neuron.

This neuronal region transmits electrical impulses away from the cell body.

Which relatively rare type of neuron has two processes extending from opposite sides of the cell body?

Which of the following is the correct path an impulse takes across a synapse?