A & P Final Review

Action potentials are sent to slow the heart's rate of contraction. The axon sending these signals will most likely belong to which division of the nervous system?

parasympathetic division

Action potentials leading to the brain carry information about cool temperatures on the skin. The axon sending these signals will most likely belong to which division of the nervous system?

sensory (afferent) division

Action potentials leading to the skeletal muscle carry information to direct movement. The axon sending these signals will most likely belong to which division of the nervous system?

somatic nervous system

Cranial nerve II, the optic nerve sends action potentials to the brain carrying information about the things we see. These axons most likely belong to which division of the nervous system?

sensory (afferent) division

The concentration of ions in the chemical environment surrounding the neurons must be tightly regulated for neurons to function properly. Which of the following cells is most responsible for this?

astrocytes

Some axons of the peripheral nervous system have the ability to regenerate after damage has occurred. Which of the following cells is most responsible for aiding in this regulation?

Schwann cells

It is important for newly developed neurons to form synapses with other neurons. Which cells are most responsible for guiding the formation of these particular junctions?

astrocytes

Meningitis can be caused by infection of the central nervous system by bacteria. Which cells would be most responsible for removing the infection?

microglia

Like all cells, the neurons' internal organization dictates its function. Neurons have relatively many mitochondria, an extensive network of rough endoplasmic reticulum and many clusters of ribosomes. These cellular features indicate all of the following EXCEPT ________.

neurons have stable, relatively unchanging internal environments

Which of the following is NOT a function of dendrites?

generate action potentials and transmit them away from the cell body

Bipolar neurons are commonly ________.

found in the retina of the eye

Which of the following is NOT a characteristic of neurons?

They are mitotic.

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

ganglia

A neuron that has as its primary function the job of connecting other neurons is called a(n) ________.

interneuron

Which of the following correctly describes a graded potential?

It can have magnitudes of various sizes.

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

generator potential

Which of the following is NOT true of graded potentials?

They increase amplitude as they move away from the stimulus point.

The interior surface of a neuron's plasma membrane at resting membrane potential will have a ________.

negative charge and contains less sodium than outside of the cell

Which of the following correctly describes a graded potential?

It can have magnitudes of various sizes.

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

generator potential

Which of the following is NOT true of graded potentials?

They increase amplitude as they move away from the stimulus point.

The interior surface of a neuron's plasma membrane at resting membrane potential will have a ________.

negative charge and contains less sodium than outside of the cell

An action potential is regarded as an example of a positive feedback. Which of the following examples below best illustrates the positive feedback aspect of an action potential?

A threshold stimulus will cause the opening of voltage gated sodium ion channels that will cause further depolarizing stimulus. This stimulus will open still more voltage gated sodium ion channels.

The depolarization phase of an action potential is punctuated by the closing of inactivation gates in the voltage gated sodium ion channels. All of the following are consequences of this inactivation EXCEPT one. Choose the statement below that is NOT a consequence of the closing of inactivating gates.

This allows for the efflux (diffusion out) of potassium ions, resulting in the repolarization of the cell.

During the relative refractory period of an action potential, a larger than normal stimulus is needed to cause another action potential. This is due to the fact that ________.

The voltage-gated potassium ion channels remain open long enough to hyperpolarize the axon membrane

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

frequency of action potentials

The period after an initial stimulus when a neuron is not sensitive to another stimulus is the ________.

absolute refractory period

Which ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials?

voltage-gated channel

Saltatory conduction is made possible by _

the myelin sheath

Immediately after an action potential has peaked, which of the following channels will open?

voltage-gated potassium channels

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.

A second action potential cannot be generated until ________.

the membrane potential has been reestablished

If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of the axon, ________.

the impulse would spread bidirectionally

Loss of function in the enzyme acetylcholine esterase would result in which of the following?

inability to destroy and remove acetylcholine from the synaptic cleft

Select the correct statement regarding chemical synapses.

The synaptic cleft uses the action potential to transmit a chemical signal to the postsynaptic cell.

If a postsynaptic neuron is stimulated to threshold by spatial summation this implies that ________.

the postsynaptic cell has many synapses with many presynaptic neurons

If a postsynaptic cell is stimulated to threshold by temporal summation this implies that ________.

a presynaptic neuron is sending frequent EPSP

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

hyperpolarization

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.

Which of the following describes the excitatory postsynaptic potential?

short distance depolarization

When a neurotransmitter like acetylcholine is acting in an excitatory manner which of the following is likely a result of the acetylcholine acting on the postsynaptic cell?

Chemically gated sodium channels will open.

When a neurotransmitter like GABA is acting in an inhibitory manner which of the following is likely a result of the GABA acting on the postsynaptic cell?

Different postsynaptic cells will have different receptors.

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

acetylcholine

Which of the following neurotransmitters is the principal inhibitory neurotransmitter of the spinal cord?

glycine

Which brain structure functions to control the autonomic nervous system and to regulate body temperature?

hypothalamus

The primary somatosensory cortex is located in the ________.

parietal lobe

What type of cells line the ventricles of the brain?

ependymal cells

What groove separates the frontal lobe from the parietal lobe?

central sulcus

Which of the following best describes the cerebrum?

executive suite

An elevated ridge of the cortex is called a ________.

gyrus

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

spinal cord may be affected

Ridges of tissue on the surface of the cerebral hemispheres are called ________.

gyri

An individual who could trace a picture of a bicycle with his or her finger but could not recognize it as a bicycle is most likely to have sustained damage to the ________.

visual association area

Broca's area ________.

is considered a motor speech area

Which part of the cerebral cortex is involved in intellect, cognition, recall, and personality?

prefrontal cortex (anterior association area)

The large commissure that connects the right and left sides of the brain is called the ________.

corpus callosum

Which brain structure functions to control the autonomic nervous system and to regulate body temperature?

hypothalamus

The brain stem consists of the ________.

midbrain, medulla, and pons

Vital centers for the control of heart rate, respiration, and blood pressure are located in the ________.

medulla oblongata

Cell bodies of sensory neurons are located in ______

the dorsal root ganglia of the spinal cord

Injury to the hypothalamus may result in all of the following EXCEPT ________.

loss of fine motor control

While sleep requirements vary, most adults need ________ hours of sleep for optimal health and function.

7-8

Degeneration of the dopamine-releasing neurons of the ________ is the ultimate cause of Parkinson's disease.

substantia nigra

If someone spills very hot coffee (200°F) on their skin, they will likely perceive much pain. Which of the following receptor types is causing this sensation?

nociceptors

Receptors that respond to changes in room temperature are found in the skin. Which of the following pairs of classifications below best fit the receptor type that is being described above?

thermoreceptors that are also exteroceptors

We can touch our finger to our nose while our eyes are closed in part because we can sense the position and movement of our joints as well as the length of stretch in our muscles. These sensations create awareness of our body's positioning. The following receptors are most likely responsible for this ability.

proprioceptors

Tactile sensation is a combination of touch, pressure, stretch, and vibration. Which of the following is most likely the receptor type that senses tactile stimulation?

mechanoreceptors

Which of the following is the best explanation of how a stimulus's strength is transmitted to the central nervous system from sensory nerves?

Action potential frequency is increased as stimulus strength increases.

Which of the following is a correct statement regarding the occurrence of a sensation?

The stimulus energy must be converted into the energy of a graded potential.

Which receptors respond to stimuli within the body?

interoceptors

Nerves that carry impulses toward the CNS only are ________.

afferent nerves

Regeneration within the CNS ________.

is prevented due to growth-inhibiting proteins of oligodendrocytes

Select the correct definition.

Question options:

A)

Magnitude estimation is the simplest level of sensation.

B)

Pattern recognition allows us to see a familiar face.

C)

Perceptual detection is the ability to detect how much stimulus is applied to the body.

D)

Spatial discrimination allows us to recognize textures.

Pattern recognition allows us to see a familiar face.

All processing at the circuit level going up to the perceptual level must synapse in the ________.

thalamus

Feeling a gentle caress on your arm would likely involve all of the following EXCEPT ________.

Lamellar corpuscles

Dermatome maps are useful to clinicians because ________.

they can help pinpoint the location of spinal injury

A patient has an injury of the spine and is now suffering from a loss of motor function in his right arm. However, he still has normal sensory function in the arm. Based on this information it is likely that the patient has nervous tissue damage located at ________.

the ventral root located at one or more of the cervical vertebra

Injury to cervical vertebrae C3-C4 is particularly problematic because ________.

the phrenic nerve that serves the diaphragm receives its fibers from here

Complicated interlacing of the ventral rami form networks called nerve plexus. The crisscrossing of the nerve fibers from the various spinal nerves is advantageous because ________.

injury to any single spinal nerve will be less damaging as there is less chance of total loss of innervation to any particular organ

Starting at the spinal cord, the subdivisions of the brachial plexus are (in order) ________.

roots, trunks, divisions, and cords

Striking the "funny bone" is actually stimulation of (or injury to) the ________.

ulnar nerve

Which nerve is compressed in carpal tunnel syndrome?

median

Mixed cranial nerves containing both motor and sensory fibers include all EXCEPT which of the following?

optic

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

Inborn or intrinsic reflexes are ______

involuntary, yet may be modified by learned behavior

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

receptor, afferent neuron, integration center, efferent neuron, effector

Preparing the body for the "fight-or-flight" response is the role of the ________.

sympathetic division

Over 90% of all parasympathetic axons are derived from cranial nerve ________.

X (vagus)

The "fight or flight" division of the autonomic nervous system is the ________.

sympathetic division

Which of these effectors is NOT directly controlled by the autonomic nervous system?

skeletal muscle

Autonomic ganglia contain ________.

the cell bodies of motor neurons