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Exam 3: Homework Questions

Terms in this set (100)

A neuron that has as its primary function the job of connecting other neurons is called a(n) ________.
Interneuron
Meningitis can be caused by infection of the central nervous system by bacteria. Which cells would be most responsible for removing the infection?
Microglia
Saltatory conduction is made possible by ________
the myelin sheath
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
The interior surface of a neuron's plasma membrane at resting membrane potential will have a ________
negative charge and contain less sodium than outside of the cell
Which of the following correctly describes a graded potential?
It can have amplitudes of various sizes.
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 nerve impulse 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
Immediately after an action potential has peaked, which of the following channels will open?
voltage-gated potassium channels
An inhibitory postsynaptic potential (IPSP) is associated with _________
hyperpolarization
If a postsynaptic cell is stimulated to threshold by temporal summation this implies that ________
a presynaptic neuron is sending frequent EPSP
If a postsynaptic neuron is stimulated to threshold by spatial summation this implies that ________
the postsynaptic cells has many synapses with many presynaptic neurons
Select the correct statement regarding chemical synapses.
The synaptic cleft uses the action potential to transmit a chemical signal to the postsynaptic cell.
The effect of acetylcholine can be stimulating or inhibiting. Which of the following gives the best explanation for why this is so?
Different postsynaptic cells will have different receptors.
What does the central nervous system use to determine the strength of a stimulus?
Frequency of action potentials
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.
Which of the following describes the excitatory postsynaptic potential?
Short distance depolarization
Which of the following is NOT a chemical class of neurotransmitters?
Nucleic acid
Which of the following is false or incorrect?
A nerve impulse occurs if the excitatory and inhibitory effects are equal.
Arachnoid granulations are knoblike projections that protrude superiorly through the ________ mater to absorb cerebrospinal fluid into venous blood.
dura
Broca's area ________.
is considered a motor speech area
Loss of ability to perform skilled motor activities such as piano playing, with no paralysis or weakness in specific muscles, might suggest damage to the ________.
premotor cortex
The brain area that regulates activities that control the state of wakefulness or alertness of the cerebral cortex is the ________.
reticular formation
The primary somatosensory cortex is located in the ________.
parietal lobe
Which brain structure functions to control the autonomic nervous system and to regulate body temperature?
Hypothalamus
Which of the following is NOT a role of the basal nuclei?
Initiating protective reflex actions
Which of the following would you NOT find in normal cerebrospinal fluid?
Red blood cells
Which of these would you NOT find in the cerebral cortex?
Fiber tracts
Which part of the cerebral cortex is involved in intellect, cognition, recall, and personality?
Prefrontal cortex (anterior association area)
All of the following are structures of the limbic system EXCEPT the ________
caudate nucleus
Cell bodies of sensory neurons are located in ________
the dorsal root ganglia of the spinal cord
Interneurons receiving input from sensory neurons are located in the ________
dorsal (posterior) horn
Second-order neurons of ascending pathways that contribute to sensory perception terminate in the ________
thalamus
Spinocerebellar tracts ________
carry information about muscle or tendon stretch to the cerebellum
The white matter of the spinal cord contains ________
myelinated and unmyelinated nerve fibers
Vital centers for the control of heart rate, respiration, and blood pressure are located in the ________
medulla oblongata
White matter is found in all of the following locations EXCEPT the ________
cerebral cortex
The blood-brain barrier is effective against ________
metabolic waste such as urea
Which of the following is NOT a function of the CSF?
initiation of some nerve impulses
A fracture of the ethmoid bone could result in damage to which cranial nerve?
Olfactory
Bell's palsy is ________
characterized by paralysis of facial muscles
Dermatome maps are useful to clinicians because ________
they can help pinpoint the location of spinal injury
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
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
Mixed cranial nerves containing both motor and sensory fibers include all EXCEPT which of the following?
Olfactory
Problems in balance may follow trauma to which nerve?
Vestibulocochlear
Which of the following is the correct simple spinal reflex arc?
Receptor, afferent neuron, integration center, efferent neuron, effector
Striking the "funny bone" is actually stimulation of (or injury to) the ________
Ulnar nerve
Select the statement that is most correct.
Ganglia associated with afferent nerve fibers contain cell bodies of sensory neurons.
Erection (vasodilation) of the penis or clitoris ________
is primarily under parasympathetic control
Sympathetic division stimulation causes ________
increased blood glucose, decreased GI peristalsis, and increased heart rate and blood pressure
The secretions of the adrenal medulla act to supplement the effects of ________
sympathetic stimulation
The smooth muscle of the digestive viscera is served largely by the ________
vagus (X) nerves
The parasympathetic tone ________
determines normal activity of the urinary tract
Sympathetic nerves may leave the spinal cord at which vertebra?
First thoracic
Preparing the body for the "fight-or-flight" response is the role of the ________
sympathetic nervous system
Parasympathetic functions include ________
lens accommodation for close vision
Over 90% of all parasympathetic fibers are derived from cranial nerve ________
X
Which of the following is mismatched?
Promotes urination; sympathetic
As light travels through the eye, it passes through several structures or chambers before reaching the retina. Which list below gives those structures in the correct order?
Cornea, anterior chamber, pupil, lens, posterior segment
Conscious perception of vision probably reflects activity in the ________
occipital lobe of the cortex
Humans can see several thousand shades of color but have cone photoreceptors that are sensitive to only three (perhaps four) wavelengths of light. What is the best explanation for why we see so many colors?
Color perception is achieved by activation of various combinations between the three cone types.
Nerve fibers from the medial aspect of each eye ________
cross over to the opposite side at the chiasma
Nutrients are delivered and waste products are carried away from the cells of the posterior segment of the eye by blood vessels. However, the cells in the cornea and lens (in the anterior segment) are avascular. Which is the best explanation for how these cells are maintained?
The aqueous humor is continuously replenished and flows from the ciliary process to drain in the scleral venous sinus.
Overlap in the visual fields of our eyes ________
allows us to subconsciously estimate the distance of objects based on the different angles the image strikes our two retinas
Paralysis of which eye muscle would prevent the right eye from looking to the left?
Medial rectus
The elasticity of the lens decreases with age. This leads to which of the following?
less accommodation of the lenses and difficulty focusing on nearby objects
There are three layers of neurons in the retina. The axons of which of these neuron layers form the optic nerves?
Ganglion cells
What is the main function of the rods in the eye?
Vision in dim light
Humans can smell as many as 10,000 different odors but have significantly fewer types of olfactory receptors. Which of the following is the best explanation for why humans can distinguish so many smells?
The sensation of a single, distinct smell is a combination of a variety of chemicals that stimulate different combinations of olfactory receptor cells all at once.
Taste buds are NOT found ________
in filiform papillae
The only special sense NOT fully functional at birth is the sense of ________
vision
The receptor membranes of gustatory cells are ________
gustatory hairs
Which best describes the function of olfactory cilia?
increase surface area of neurons receptive to airborne chemicals
Which of the following is true about gustatory receptors?
Complete adaptation occurs in about one to five minutes.
Which of the following is NOT a characteristic of olfactory receptor cells?
They are unipolar neurons.
Which of the following taste sensations is incorrectly matched to the chemicals that produce it?
Umami-triglycerides and fatty acids
Which of the following types of neurons are replaced throughout adult life?
Olfactory receptor cells
Which of the following types of receptors are located in the mouth?
chemoreceptors, mechanoreceptors, thermoreceptors, and nociceptors
A perceived increase in the volume of sound is best explained by ________
an increase in the height of the sound wave
An essential part of the maculae involved in static equilibrium is (are) the ________
otoliths
Fusing of the ossicles (otosclerosis) results in ________
conduction deafness
Labyrinthitis is a medical condition often caused by a viral infection, resulting in swelling and inflammation of the membranous labyrinth. Which of the following symptoms would you most associate with the condition of labyrinthitis?
Loss of balance and dizziness
Motion sickness seems to ________
result from mismatch between visual and vestibular inputs
Receptors for hearing are located in the ________
cochlea
Select the correct statement about equilibrium.
Cristae respond to angular acceleration and deceleration
The sensation of loudness or the volume of a sound is detected by ________
greater movement of the basilar membrane resulting in greater deflection of the hair cells
Tom is a 45-year-old male that has lost his ability to hear high frequency sounds. The most likely explanation for this would be ________
damage to the hair cells near the oval window in the cochlear duct
What is the primary function of cerumen?
cleans and lubricates the external auditory canal
A man has been told that he is NOT synthesizing enough follicle-stimulating hormone (FSH), and for this reason he may be unable to father a child. Choose the correct statement to explain this problem.
FSH stimulates sperm production in the testes.
At age 85, Lyle's immune system does not respond to vaccines as well as it did when he was younger. The atrophy of which endocrine gland is likely responsible for this?
Thymus
During an afternoon class, Lisa starts to feel hungry and worries that her blood sugar level may be dropping. Which hormone is helping to prevent a drop in blood sugar level?
Glucagon
Several hormones are synthesized in the hypothalamus and transported to the anterior pituitary gland. The mechanism of transportation from hypothalamus to anterior pituitary gland is through the ________
hypophyseal portal system
Steroid hormones exert their action by ________
entering the nucleus of a cell and initiating or altering the expression of a gene
The ability of a specific tissue or organ to respond to the presence of a hormone is dependent on ________
the presence of the appropriate receptors on the cells of the target tissue or organ
The single most important regulator of calcium levels in the blood is ________
parathyroid hormone
Upon landing at the airport in Lagos, Nigeria, Eric feels wide awake even though the local time is 11pm. Which synthetic hormone supplement could he administer to help adjust to the new time zone?
Melatonin
Which of the following hormones suppresses appetite and increases energy expenditure?
Leptin
Which of the following is correctly matched?
Zona reticularis — gonadocorticoids
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