Anatomy Exam 3 Flashcards

Questions and Answers

Which of the following correctly describes a graded potential?

Membrane potential reversal

Constant amplitude

Amplitude of various sizes (correct)

Action potential

Second-order neurons of both the specific and nonspecific ascending pathways terminate in the ________.

thalamus

Spinal nerves exiting the cord from the level of L4 to S4 form the ________.

sacral plexus

Place the meninges and associated spaces in order from most superficial to deepest.

4, 5, 6, 3, 1, 2 Signup and view all the answers

The arbor vitae refers to ________.

cerebellar white matter Signup and view all the answers

At a chemical synapse, what describes the communication between two cells?

Two cells are in direct contact and communicate using gap junctions. Signup and view all the answers

Neural tracts that convey life-saving information to the brain concerning burning pain would be ________.

lateral spinothalamic Signup and view all the answers

Which of the following is NOT part of a reflex arc?

Infarent transmission corpuscle Signup and view all the answers

Collections of nerve cell bodies outside the central nervous system are called ________.

ganglia Signup and view all the answers

Tremor at rest, shuffling gait, stooped posture, and expressionless face are characteristics of ________.

Parkinson's disease Signup and view all the answers

Graded potentials occur when ions move across a membrane in dendrites/the soma and cause a minor change in the resting membrane potential.

True Signup and view all the answers

Bipolar neurons are commonly ________.

found in the retina of the eye Signup and view all the answers

Schwann cells are functionally similar to ________.

Oligodendrocytes Signup and view all the answers

Inborn or intrinsic reflexes are ________.

involuntary, yet may be modified by learned behavior Signup and view all the answers

Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?

A single type of channel will open, permitting simultaneous flow of sodium and potassium Signup and view all the answers

The term central nervous system refers to the ________.

brain and spinal cord Signup and view all the answers

White matter is found in all of the following locations except the ________.

Cerebral cortex Signup and view all the answers

Which of the following is true about the movement of ions across excitable living membranes?

Sodium gates in the membrane can open in response to electrical potential changes Signup and view all the answers

Which of the following is an incorrect statement regarding the occurrence of a sensation?

It has a direct impact on motor neurons Signup and view all the answers

In order for a neuron to regenerate, it must be in the peripheral nervous system.

True Signup and view all the answers

Which of these would you not find in the cerebral cortex?

Fiber tracts Signup and view all the answers

Saltatory conduction is made possible by ________.

the myelin sheath Signup and view all the answers

Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?

Acetylcholine Signup and view all the answers

Potentially damaging stimuli that result in pain are selectively detected by ________.

nociceptors Signup and view all the answers

What is the role of acetylcholinesterase?

Destroy ACh a brief period after its release by the axon endings. Signup and view all the answers

Nerve cell adhesion molecules (N-CAMs) are ________.

crucial for the development of neural connections Signup and view all the answers

Which of the following is not a function of astrocytes?

Forming myelin sheaths Signup and view all the answers

A second nerve impulse cannot be generated until ________.

the membrane potential has been reestablished Signup and view all the answers

Each of the following is an amino acid that functions as a neurotransmitter EXCEPT:

Dopamine Signup and view all the answers

The subarachnoid space lies between what two layers of meninges?

arachnoid and pia Signup and view all the answers

Which neuroglia cells produce myelin?

Oligodendrocytes & Schwann cells Signup and view all the answers

When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ________.

generator potential Signup and view all the answers

Place the events involved in generating an action potential in the order in which they occur.

6, 2, 4, 8, 3, 1, 5, 7 Signup and view all the answers

Regeneration within the CNS ________.

is prevented due to growth-inhibiting proteins of oligodendrocytes. Signup and view all the answers

Which of the following is not characteristic of neurons?

They are mitotic Signup and view all the answers

Which of the following describes the excitatory postsynaptic potential?

Short distance depolarization Signup and view all the answers

Which of the following is not a function of the autonomic nervous system?

Innervation of skeletal muscle Signup and view all the answers

If the caudal portion of the neural tube failed to develop properly the ________.

spinal cord may be affected Signup and view all the answers

In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment?

The interior is negatively charged and contains less sodium. Signup and view all the answers

Which of the following is not a function of the CSF?

Initiation of some nerve impulses Signup and view all the answers

A reflex that causes muscle relaxation and lengthening in response to muscle tension is called a ________.

tendon reflex Signup and view all the answers

Which of the following is not a main level of neural integration in the somatosensory system?

Segmental Signup and view all the answers

An impulse from one nerve cell is communicated to another nerve cell via the ________.

synapse Signup and view all the answers

Axons classified as A fibers

Are myelinated & have large diameters Signup and view all the answers

If the ventral root of a spinal nerve were cut, what would be the result in the tissue or region that nerve supplies?

A complete loss of voluntary movement. Signup and view all the answers

Nerves that carry impulses toward the CNS only are ________.

afferent nerves Signup and view all the answers

The substance released at axon terminals to propagate a nervous impulse is called a(n) ________.

neurotransmitter Signup and view all the answers

Select the statement that is most correct.

Ganglia associated with afferent nerve fibers contain cell bodies of sensory neurons. Signup and view all the answers

What does the central nervous system use to determine the strength of a stimulus?

frequency of action potentials Signup and view all the answers

Which of the following correctly describes a function of the nervous system?

All of the above Signup and view all the answers

The somatic nervous system provides motor signals and conscious control to skeletal muscles.

True Signup and view all the answers

An inhibitory postsynaptic potential (IPSP) is associated with ________.

hyperpolarization Signup and view all the answers

The peripheral nervous system may be divided into somatic, autonomic, and enteric nervous systems.

True Signup and view all the answers

Which of the following is NOT true?

Most neurons have many axons and one dendrite Signup and view all the answers

After axonal injury, regeneration in peripheral nerves is guided by ________.

Schwann cells Signup and view all the answers

Which of the following is not true of graded potentials?

They are all-or-nothing responses Signup and view all the answers

Which of the following is the correct simple spinal reflex arc?

Receptor, afferent neuron, integration center, efferent neuron, effector Signup and view all the answers

Each is part of the nervous system EXCEPT the:

Vertebral Column Signup and view all the answers

Which of the following would you not find in normal cerebrospinal fluid?

Red blood cells Signup and view all the answers

Action potentials allow an impulse to travel over long distances.

True Signup and view all the answers

Electrical synapses occur when _____?

There is direct contact between electrically excitable cells Signup and view all the answers

The part of a neuron that conducts impulses away from its cell body is called a(n) ________.

axon Signup and view all the answers

Which of the following is true of nerve impulse conduction?

Continuous conduction is slower than saltatory conduction Signup and view all the answers

In order for a neuron to regenerate.

Both A and B Signup and view all the answers

Neuroglia (glial cells)

All of the above Signup and view all the answers

Neuroglia that control the chemical environment around neurons by buffering potassium and recapturing neurotransmitters are ________.

astrocytes Signup and view all the answers

Immediately after an action potential has peaked, which cellular gates open?

Potassium Signup and view all the answers

Select the correct statement regarding synapses.

The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another. Signup and view all the answers

Which of the following is false or incorrect?

A nerve impulse occurs if the excitatory and inhibitory effects are equal Signup and view all the answers

Study Notes

Graded Potentials and Neuron Function

Graded potentials vary in amplitude due to changes in ion movement across membranes, occurring in dendrites or soma.
Excitatory postsynaptic potentials (EPSPs) involve sodium and potassium ions across a single channel, causing short-distance depolarization.
Inhibitory postsynaptic potentials (IPSPs) lead to hyperpolarization of the neuron.

Neural Pathways and Anatomy

Second-order neurons of ascending pathways terminate in the thalamus, which relays sensory information.
The sacral plexus is formed by spinal nerves exiting from L4 to S4.
Meninges are layered as follows: epidural space, dura mater, subdural space, arachnoid mater, subarachnoid space, and pia mater.

Nerve Cells and Their Functions

The arbor vitae refers to the structure of cerebellar white matter.
Collections of nerve cell bodies outside the CNS are known as ganglia.
Bipolar neurons are predominantly found in the retina.
Schwann cells and oligodendrocytes are responsible for myelination in the PNS and CNS, respectively.

Reflexes and Response Mechanisms

Inborn reflexes occur involuntarily but can be modified through learning experiences.
Reflex arcs follow the order: receptor, afferent neuron, integration center, efferent neuron, and effector.
Tendon reflex causes muscle relaxation in response to muscle tension.

Neurotransmitters and Signaling

Acetylcholine is the main excitatory neurotransmitter for skeletal muscle activation.
Acetylcholinesterase rapidly breaks down acetylcholine post-release.
Sensory neurons initiate graded potentials known as generator potentials.

CNS and PNS Characteristics

The central nervous system comprises the brain and spinal cord, while the peripheral nervous system is divided into somatic, autonomic, and enteric systems.
Astrocytes regulate chemical environments for neurons and buffer potassium levels.
Most neurons are not mitotic and do not have multiple axons.

Action Potentials and Impulse Conduction

Action potentials allow rapid impulse transmission over long distances and occur after specific ionic changes.
Sodium channels open first during depolarization, followed by potassium channels for repolarization.
Saltatory conduction, facilitated by myelin sheaths, increases conduction speed compared to continuous conduction.

Development and Injury Response

Neuronal regeneration is possible in the peripheral nervous system if the cell body remains intact.
Growth-inhibiting proteins in the oligodendrocytes prevent regeneration in the CNS.

Conditions Affecting Neurons

Tremors, shuffling gait, and stooped posture are indicative of Parkinson's disease.
Nociceptors specifically detect potentially damaging stimuli leading to pain sensations.

cerebrospinal Fluid and Nervous System Functions

CSF plays key roles, but it does not initiate nerve impulses and should not contain red blood cells.
Frequency of action potentials determines the perceived strength of stimuli.

Integration and Communication

The neural integration process involves sensory detection, processing, and motor response formation.
Electrical synapses enable rapid communication and synchronization through direct contact between cells.

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Description

Test your knowledge with these anatomy flashcards focused on key concepts relevant to Exam 3. Each card covers important definitions and descriptions such as graded potentials and neural pathways. Perfect for students preparing for their anatomy exams.