Question 1

Which of the following kinds of neurons are NOT generally cholinergic?

Accepted Answer

Postganglionic sympathetic neurons typically release norepinephrine as their primary neurotransmitter, not acetylcholine.

Question 2

Which is one of the most abundant excitatory neurotransmitters in the CNS?

Accepted Answer

Glutamate is one of the most abundant excitatory neurotransmitters in the CNS, involved in a range of processes including learning and memory. Dopamine and norepinephrine are both monoamine neurotransmitters, with dopamine involved in reward and motivation, and norepinephrine in alertness and arousal. GABA is an inhibitory neurotransmitter, while endorphins are neuropeptides involved in pain relief and pleasure.

Question 3

The lipid portion of a cell's plasma membrane constitutes a barrier to current.

Accepted Answer

The lipid portion of the plasma membrane, which is mainly composed of phospholipids, creates a barrier to the flow of ions and charged molecules, making it selectively permeable to certain substances. This property allows the membrane to regulate the entry and exit of molecules, maintain cell homeostasis, and perform other specialized functions.

Question 4

Postganglionic neuron cell bodies of the autonomic nervous system have which category of neurotransmitter receptor?

Accepted Answer

Postganglionic neuron cell bodies of the autonomic nervous system have nicotinic acetylcholine receptors, which are activated by acetylcholine released from preganglionic neurons.

Question 5

Which of the following is NOT characteristic of the sympathetic division of the autonomic nervous system?

Accepted Answer

In the sympathetic division of the autonomic nervous system, preganglionic neurons are typically short, and the ganglia where they synapse are located close to the spinal cord, not in or near the effector target tissues.

Question 6

Excessive alcohol intake can cause difficulty maintaining posture and coordinating body movements.This is likely due to alcohol's effect stimulatory effect on GABA-releasing neurons in the

Accepted Answer

The cerebellum is responsible for posture and coordination of body movements, and excessive alcohol intake can impair its function. Alcohol affects the inhibitory neurotransmitter GABA, which is involved in the regulation of cerebellar circuits. This leads to decreased activity in the cerebellum, resulting in difficulty maintaining posture and coordinating body movements.

Question 7

The central nervous system includes the

Accepted Answer

The central nervous system consists of the brain and spinal cord, which are responsible for processing and coordinating sensory and motor signals throughout the body. The other options either include peripheral nerves or specific subdivisions of the nervous system, but do not encompass the entire central nervous system.

Question 8

A patient has been experiencing difficulty with homeostatic regulation.  An MRI scan reveals a brain tumor.Which brain region is the tumor likely in?

Accepted Answer

The hypothalamus is responsible for homeostatic regulation, including the regulation of body temperature, hunger, thirst, and hormone secretion. If there is a tumor in this region, it can disturb the normal function of the hypothalamus and lead to dysregulation of various physiological processes.

Question 9

Which best describes the reticular formation of the brain?

Accepted Answer

The reticular formation is a network of nuclei and fibers that extends throughout the brainstem and into the thalamus. It plays a key role in regulating sleep and wakefulness, as well as integrating information from all regions of the central nervous system (CNS). It is not primarily involved in motor coordination and balance (A), endocrine regulation (B), or visual perception (C). Additionally, it is not the primary synaptic relay station for sensory information entering the CNS (E).

Question 10

A myelinated axon is shielded from direct contact with the extracellular fluid all along its length.

Accepted Answer

Myelinated axons have gaps known as nodes of Ranvier where the axon is exposed to the extracellular fluid, allowing for ion exchange necessary for the propagation of action potentials.

Question 11

Which is one of the major inhibitory neurotransmitters in the CNS?

Accepted Answer

Gamma-aminobutyric acid (GABA) is one of the major inhibitory neurotransmitters in the CNS. It works by binding to GABA receptors on neurons, which reduces their excitability and ultimately reduces the likelihood of producing an action potential.

Question 12

Multiple sclerosis is a disease that primarily effects the somatic motor nervous system.  Which of the following might be symptoms of multiple sclerosis?

Accepted Answer

Multiple sclerosis affects the somatic motor nervous system, leading to difficulty in controlling voluntary muscle movements, such as using a fork and knife.

Question 13

Which of the following does NOT result from the binding of nicotine with nicotinic acetylcholine receptors?

Accepted Answer

Nicotine binding with nicotinic acetylcholine receptors can result in signal transmission at neuromuscular junctions, generation of excitatory signals within autonomic ganglia, the release of norepinephrine, dopamine, and epinephrine, and facilitation of the release of multiple neurotransmitters within the brain, including the "reward pathway" involving dopamine. However, nicotine binding does not result in mild form of skeletal muscle paralysis.

Question 14

You are studying a disease in which inhibition of sensory neurons is diminished,leading to more dramatic sensory sensations than are appropriate for stimulus strength.For example,when a person with this disease listens to a person talking in a normal voice,it sounds like they are yelling.  Which neurotransmitter might be expressed at lower levels in this disease compared to a healthy individual?

Accepted Answer

Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter that is responsible for reducing neural excitability. If its inhibition is diminished, as in this disease, the sensory neurons will be more excitable, and there will be more dramatic sensory sensations than appropriate for stimulus strength.

Question 15

Synthesis of neuropeptides differs from that of other neurotransmitters because it

Accepted Answer

Neuropeptides are synthesized in the cell bodies of neurons, unlike many other neurotransmitters that are synthesized in the axon terminals. This is because neuropeptides are synthesized as larger precursor proteins on ribosomes and then processed into their active form, a process that occurs in the cell body before they are transported to the axon terminals.

Question 16

In clinical trials,scientists discover that use of drug X results in a decrease in norepinephrine signaling.In the process of making a list of possible mechanisms of this drug to test,which of the following is NOT a plausible explanation for the effects of drug X?

Accepted Answer

Blocking the reuptake of norepinephrine would increase, not decrease, norepinephrine signaling by allowing it to remain in the synaptic cleft longer and continue to activate its receptors.

Question 17

Which is a FALSE statement about the cerebrospinal fluid?

Accepted Answer

The cerebrospinal fluid (CSF) doesn't have the same composition as blood plasma, it has a different composition with fewer proteins and more sodium and chloride ions.

All other options (B, C, D, and E) are true statements about the CSF.

Question 18

The fire alarm in your building is sounding off and you are hurriedly collecting your belongings before evacuating.  Which portion of the nervous system is dominant?

Accepted Answer

The sympathetic nervous system is responsible for the fight or flight response, which is activated in times of stress or danger. The sound of a fire alarm triggering an evacuation would qualify as a stressful situation, meaning the sympathetic nervous system is dominant. It prepares the body to respond to this stress by increasing heart rate, dilating pupils, and releasing adrenaline.

Question 19

The portion of the peripheral nervous system that is composed of nerve fibers that innervate skeletal muscle is called the

Accepted Answer

The somatic motor nervous system is responsible for the innervation of skeletal muscle, which is generally under voluntary control. The afferent nervous system is responsible for conveying sensory information from the periphery to the central nervous system, while the sympathetic and parasympathetic nervous systems are components of the autonomic nervous system, which regulates involuntary processes such as heart rate, digestion, and respiration.

Question 20

When you have a negative experience,your brain ties the emotion to the memory so that you avoid similar experiences in the future.  If you were in a bike accident,and were afraid to get on a bike again,which brain structure functional group is active in guiding your fear?

Accepted Answer

The limbic system is responsible for regulating emotions and memory formation. Fearful memories are often stored in this region and can be a significant factor in guiding behavior in the future.

Quiz 6: Neuronal Signaling and the Structure of the Nervous System