Practice Quiz Unit 3 Flashcards
According to Ohm’s law, current is
directly related to voltage and inversely related to resistance.
The connective tissue wrapping that surrounds bundles (fascicles) of axons is the
perineurium
(NOT epineurium)
The glial cell that myelinates and insulates axons within the CNS is the
oligodendrocyte
The type of neuronal circuit in which several nerve impulses come together at a single postsynaptic neuron is a _____________ circuit.
converging
The shallow depressions between folds on the surface of the brain are called
sulci.
The medulla oblongata contains a cardiac center and a medullary respiratory center.
true
What is the name of the brainstem sensory area that contains axons that project to the cerebral cortex to arouse us from sleep?
Reticular activating system
The cerebral cortex consists of ______ matter.
gray
Which cranial nerve is composed of only motor fibers?
VI
The cell bodies of sensory neurons are located in the
posterior root ganglion.
What is the thin strand of pia mater that helps to anchor the spinal cord to the coccyx?
Filum terminale
Stepping on a piece of glass would most likely invoke a _____ reflex.
withdrawal
The tapered, conical inferior end of the spinal cord is called the conus
medullaris
The inferior tip of the spinal cord is the ___________ part.
coccygeal
Which divisionfunctions to increase alertness and direct bodily responses in stressful situations?
Sympathetic
Which type of innervation causes the heart rate to increase?
Sympathetic
Neuronal ___ occurs when axons from numerous preganglionic cells synapse on a single ganglionic cell.
convergence
The “fight-or-flight” system is the ___ nervous system.
sympathetic
These receptors respond to changes in temperature.
Thermoreceptors
Phototransduction is the process in which
photoreceptors convert light energy to changes in membrane potential.
Our ability to precisely locate a stimulus is ___ proportional to receptive field size.
inversely
A receptor that is wrapped in connective tissue is referred to as being
encapsulated
Distortion of hair cells in the cochlea causes
initiation of action potentials in CN VIII
The glossy-white appearance of most axons is due to
the high lipid content of the myelin sheath
A mixed nerve is one that contains both
sensory and motor neurons.
The type of neuronal circuit in which several nerve impulses come together at a single postsynaptic neuron is a _____________ circuit.
converging
Conductive activity in a neuron generally causes it to secrete
a specific neurotransmitter that either excites or inhibits its target.
Generally, the left cerebral hemisphere issues motor commands for the right side of the body.
true
Which structure serves as the main relay point for sensory information that is headed to a primary sensory region of the cerebral cortex?
Thalamus
The type of glial cell that plays a critical role in the formation of CSF is the ___ cell
ependymal
Which is not a function of cerebrospinal fluid?
CSF helps to promote mitosis within neuronal tissue.
Which secondary brain vesicle forms the portion of the adult brain that includes the epithalamus, thalamus, and hypothalamus?
Diencephalon
The deepest and most delicate of the meninges, adhered directly to the spinal cord, consists of elastic and collagen fibers. It is called the
pia mater.
Stepping on a piece of glass would most likely invoke a _____ reflex.
withdrawal
The most inferior spinal nerve is
Co1.
Motor pathways are _________ tracts that control _________.
descending; effectors
The _______ nuclei within the gray matter of the spinal cord send nerve impulses to skeletal muscles.
somatic motor
In the stress response, the process by which many structures are activated simultaneously is known as ___ activation.
mass
White rami appear white in color due to the fact that they are
myelinated
Which division functions to increase alertness and direct bodily responses in stressful situations?
Sympathetic
Which division functions to conserve energy and replenish the supply of nutrients?
Parasympathetic
These receptors respond to touch, pressure, vibration, and stretch.
Mechanoreceptors
By definition, transducers
change one form of energy into another form.
The gelatinous mass inside of the eye is called the
vitreous humor.
The conjunctiva that lines the internal surface of the eyelids is termed the _____ conjunctiva.
palpebral
Sharp, color vision is a result of the function of
cones.
The function of myelin is to
produce faster nerve impulse propagation.
A nerve
is a cablelike bundle of parallel axons
The type of neuronal circuit that spreads information from one presynaptic neuron to several postsynaptic neurons is a _____________ circuit.
diverging
The main way acetylcholine is cleared from a synapse is by
degradation by an enzyme
Association tracts
connect different regions of the cerebral cortex within the same hemisphere
The shallow depressions between folds on the surface of the brain are called
sulci
The ______ hemisphere is known for its involvement in categorization, symbolization, and analytical reasoning.
left
The cranial nerve that innervates smooth muscle and glands of the heart, lungs, larynx, trachea, and most abdominal organs is the ___________ nerve.
vagus
The cell bodies of sensory neurons are located in the
posterior root ganglion.
The nerves projecting inferiorly from the spinal cord are collectively called the
cauda equina.
Motor neurons of the autonomic nervous system
can either excite or inhibit effector organs.
The centers for cardiac, digestive, and vasomotor functions are housed within the
brainstem.
When ACh binds to nicotinic receptors, it
always produces an excitatory response.
The conjunctiva that lines the internal surface of the eyelids is termed the _____ conjunctiva.
palpebral
A receptor that is wrapped in connective tissue is referred to as being ___
encapsulated
Which sequence correctly traces the pathway of aqueous humor in the eye?
a: Aqueous humor is secreted by epithelial ciliary cells.
b: Aqueous humor is released into the posterior chamber.
c: Aqueous humor is drained into the scleral venous sinus.
d: Aqueous humor washes over the lens and then passes through the pupil into the anterior chamber.
a, b, d, c
Which photoreceptor cells are more numerous?
Rods
These receptors detect specific molecules in our external and internal environments.
Chemoreceptors
