Question 1

Ions other than Na⁺,K⁺,and Cl^- play no role in generating the resting membrane potential of a cell.

Accepted Answer

Other ions such as Ca2+, Mg2+, and proteins also play a role in generating the resting membrane potential of a cell.

Question 2

The region of the brain that is the most important control area for homeostatic regulation of the internal environment is:
A)the thalamus.
B)the hippocampus.
C)the cerebrum.
D)the cerebellum.
E)the hypothalamus.

Accepted Answer

The hypothalamus is the most important control center for homeostatic regulation of the body. It controls and regulates a range of autonomic functions, including temperature regulation, thirst, hunger, and fatigue. It also plays a role in regulating the endocrine system by controlling the release of hormones from the pituitary gland.

Question 3

The central nervous system includes the:
A)afferent nerves and spinal cord.
B)efferent nerves and spinal cord.
C)autonomic nervous system and the brain.
D)brain stem and the autonomic nervous system.
E)brain and spinal cord.

Accepted Answer

The central nervous system consists of the brain and spinal cord. The afferent and efferent nerves are part of the peripheral nervous system, while the autonomic nervous system is a division within the peripheral nervous system. The brain stem is also part of the brain.

Question 4

Which is a FALSE statement about the cerebrospinal fluid?
A)It has the same composition as blood plasma.
B)It acts as a cushion for the brain and spinal cord.
C)It is secreted by cells lining the ventricles of the brain.
D)It circulates within and between brain ventricles and surrounds the spinal cord.
E)It is in diffusion equilibrium with the extracellular fluid of the central nervous system.

Accepted Answer

The cerebrospinal fluid does not have the same composition as blood plasma. It has a different balance of ions and protein content.

Question 5

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

Accepted Answer

The lipid portion, also known as the lipid bilayer or phospholipid bilayer, of a cell's plasma membrane is nonconductive and acts as a physical barrier to ion flow, creating an electrical insulation that prevents current from passing through the membrane.

Question 6

The maintenance of a resting potential in a neuron depends indirectly upon the functioning of the Na⁺,K⁺-ATPase pumps in the membrane.

Accepted Answer

The Na+/K+ ATPase pumps in the membrane are responsible for maintaining the resting potential in a neuron by pumping out 3 Na+ ions for every 2 K+ ions brought in. This creates an electrochemical gradient that is essential for the proper functioning of the neuron.

Question 7

Which of the following kinds of neurons is not generally cholinergic?
A)somatic motor neurons
B)postganglionic sympathetic neurons
C)postganglionic parasympathetic neurons
D)preganglionic sympathetic neurons
E)preganglionic parasympathetic neurons

Accepted Answer

Postganglionic sympathetic neurons are generally adrenergic, releasing norepinephrine, rather than cholinergic.

Question 8

Which best describes the reticular formation of the brain?
A)It is mainly involved in motor coordination and balance.
B)It is the master endocrine gland of the brain.
C)It is primarily responsible for visual perception.
D)It integrates information from all regions of the CNS,and incorporates the mechanisms that regulate sleep and wakefulness.
E)It is the primary synaptic relay station for sensory information entering the CNS.

Accepted Answer

The reticular formation integrates information from all regions of the CNS and incorporates the mechanisms that regulate sleep and wakefulness. It is not primarily involved in motor coordination and balance (A), is not the master endocrine gland of the brain (B), is not primarily responsible for visual perception (C), and is not the primary synaptic relay station for sensory information entering the CNS (E).

Question 9

Because so many Na ions move into a cell during an action potential and so many K ions move out,no further action potentials can be generated in a given membrane until the Na,K-ATPase pumps can restore the concentration gradient.

Accepted Answer

During an action potential, the number of Na⁺ and K⁺ ions that move across the membrane is relatively small compared to the total number of ions inside and outside the cell, so the concentration gradients of Na⁺ and K⁺ are not significantly disrupted. The cell can generate multiple action potentials before the Na⁺,K⁺-ATPase pumps need to significantly restore the ion gradients.

Question 10

The ________________ is best described as "an interconnected group of brain structures including parts of the frontal lobe-cortex,temporal lobe,thalamus,and hypothalamus,that is associated with learning,emotional experience,and behavior?"
A)diencephalon
B)cerebrum
C)limbic system
D)reticular formation
E)cerebellum

Accepted Answer

The description provided matches the function and structures of the limbic system. The diencephalon is a broader term that includes the thalamus and hypothalamus but does not encompass the other structures mentioned. The cerebrum is the largest part of the brain and is responsible for voluntary actions, thought, and perception, but it does not specifically deal with emotional experience and behavior. The reticular formation is involved in regulating arousal and consciousness, but not specifically learning and emotion. The cerebellum is responsible for motor control and coordination.

Question 11

Which of the following is NOT characteristic of the sympathetic division of the ANS?
A)Preganglionic neurons tend to be long,with the ganglion located in or near the effector target tissue(s).
B)Preganglionic neurons are short and synapse in ganglia located near the spinal cord.
C)Preganglionic neurons release acetylcholine at synapses with postganglionic neurons.
D)Postganglionic neurons release norepinephrine at their neuroeffector junctions.
E)Postganglionic neuron cell bodies are located in the collateral chain ganglia (sympathetic trunk).

Accepted Answer

The answer of Which of the following is NOT characteristic...

Question 12

Which of the following does NOT result from the binding of nicotine with nicotinic acetylcholine receptors?
A)a mild form of skeletal muscle paralysis that creates a more relaxed state
B)signal transmission at neuromuscular junctions
C)generation of excitatory signals within autonomic ganglia
D) the release of norepinephrine,dopamine,and epinephrine
E)facilitation of the release of multiple neurotransmitters within the brain,including the "reward pathway" involving dopamine

Accepted Answer

The binding of nicotine with nicotinic acetylcholine receptors can lead to 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, it does not result in a mild form of skeletal muscle paralysis.

Question 13

The portion of the peripheral nervous system that is composed of nerve fibers that innervate skeletal muscle is called the:
A)afferent nervous system.
B)sympathetic nervous system.
C)parasympathetic nervous system.
D)somatic motor nervous system.
E)autonomic nervous system.

Accepted Answer

The somatic motor nervous system is responsible for controlling skeletal muscle movement through the innervation of motor neurons. The afferent nervous system is responsible for bringing sensory information to the central nervous system, while the sympathetic and parasympathetic nervous systems are part of the autonomic nervous system and are involved in regulating involuntary processes such as heart rate and digestion.

Question 14

Drug X interferes with the action of norepinephrine at synapses.Which of the following mechanisms would not explain the effects of X?
A)X inhibits synthesis of norepinephrine at the axon terminal.
B)X inhibits norepinephrine release from the terminal.
C)X blocks reuptake of norepinephrine by the terminal.
D)X is an adrenergic receptor antagonist.
E)X stimulates the catabolism of norepinephrine.

Accepted Answer

Blocking reuptake of norepinephrine would increase its action at synapses, not interfere with it.

Question 15

A graded potential in a membrane results in an electric current along an adjacent area of membrane and this current diminishes with distance from the site of the initial potential change.

Accepted Answer

Graded potentials are localized changes in membrane potential that spread passively across the membrane. As the potential spreads, it creates an electric current along the adjacent area of the membrane, but this current decreases in amplitude as it moves further away from the site of the initial potential change. This is due to the passive decay of the electrical signal as it moves through the resistance of the cell membrane.

Question 16

During a hyperpolarizing graded potential,positively charged ions flow away from the site of the initial hyperpolarization on the outside of membrane and toward this site on the inside.

Accepted Answer

The answer of During a hyperpolarizing graded potential,positively charged ions...

Question 17

Synthesis of neuropeptides differs from that of other neurotransmitters because it:
A)takes place in the axon terminals of neurons.
B)takes place in the cell bodies of neurons.
C)takes place on ribosomes in the postsynaptic cell's membrane.
D)uses amino acids as precursor molecules.
E)only takes place at synapses outside the central nervous system.

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 18

Postganglionic neuron cell bodies of the autonomic nervous system have which category of neurotransmitter receptor?
A)Adrenergic receptor
B)Serotonin receptors
C)Muscarinic acetylcholine receptors
D)Nicotinic acetylcholine receptors
E)Dopamine receptors

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 19

The cerebellum:
A)is important for coordinating body movement.
B)is the gray matter covering the entire surface of the brain.
C)is the same thing as the brain stem.
D)is in the anterior portion of the brain,just above the eyes.
E)is one of the basal nuclei that is found deep inside the cerebrum.

Accepted Answer

The cerebellum is a brain structure located at the base of the brain, below the cerebrum. It is responsible for coordinating body movement, balance, and posture.

Question 20

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.

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

Ions other than Na+,K+,and Cl- play no role in generating the resting membrane potential of a cell.

The region of the brain that is the most important control area for homeostatic regulation of the internal environment is:

The central nervous system includes the:

Which is a FALSE statement about the cerebrospinal fluid?

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

The maintenance of a resting potential in a neuron depends indirectly upon the functioning of the Na+,K+-ATPase pumps in the membrane.

Which of the following kinds of neurons is not generally cholinergic?

Which best describes the reticular formation of the brain?

Because so many Na ions move into a cell during an action potential and so many K ions move out,no further action potentials can be generated in a given membrane until the Na,K-ATPase pumps can restore the concentration gradient.

The ________________ is best described as "an interconnected group of brain structures including parts of the frontal lobe-cortex,temporal lobe,thalamus,and hypothalamus,that is associated with learning,emotional experience,and behavior?"

Which of the following is NOT characteristic of the sympathetic division of the ANS?

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

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

Drug X interferes with the action of norepinephrine at synapses.Which of the following mechanisms would not explain the effects of X?

A graded potential in a membrane results in an electric current along an adjacent area of membrane and this current diminishes with distance from the site of the initial potential change.

During a hyperpolarizing graded potential,positively charged ions flow away from the site of the initial hyperpolarization on the outside of membrane and toward this site on the inside.

Synthesis of neuropeptides differs from that of other neurotransmitters because it:

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

The cerebellum:

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

Ions other than Na⁺,K⁺,and Cl^- play no role in generating the resting membrane potential of a cell.

The maintenance of a resting potential in a neuron depends indirectly upon the functioning of the Na⁺,K⁺-ATPase pumps in the membrane.