Chapters 10 to 17 Flashcards
A stimulus that changes post synaptic neurons membrane from resting potential to -85mV is
An inhibitory stimulus
Branches that may occur along an axon are called
Collaterals
Each of the following is an example of a neuroeffector junction, except the junction between a neuron and a
Nerve cell.
A genetic disease causes the body to produce antibodies that compete withe acetylcholine for receptors on the motor end plate. Patients with this disease exhibit varying degrees of muscle weakness and flaccid paralysis in the affected muscles. If you could administer a drug the inhibits acetylcholinesterase or a drug that blocks acetylcholine which one would you use to alleviate these symptoms?
Case of competition between acetylcholine and antibodies. To ensure acetylcholine is more effective a drug that inhibits acetylcholinesterase slows breakdown of acetylcholine relieving some weakness. Acetylcholine blocker would be worse than no treatment.
During the recovery period the bodies need for oxygen is increased because
Additional oxygen is required to restore energy reserves consumed during exercise
Describe a motor unit? How many fibre units does a muscle unit contain?
A motor unit consists of all the skeletal muscle fibres controlled by a single motor neuron. They may have as few as 10 fibres or as many as 10,000
Damage to which of the following muscles would interfere most with the ability to breathe?
Intercostals
Cross bridge detachment is caused by —- binding to the myosin head.
ATP
At rest active sites on the actin are blocked by
Tropomyosin molecules
Damage to ependymal cells would most likely affect the
Formation of cerebrospinal fluid
During activities requiring aerobic endurance
Most of the muscles energy is produced in mitochondria.
Cross-bridges are portions of
Myosin molecules
A patient takes a medication that blocks ACh receptors of skeletal muscle fibres. What is this drugs effect on skeletal muscle contraction?
Reduces the muscles ability for contraction
A change in the conditions in the synaptic terminal can influence the soma as a result of —– axoplasmic transport?
Retrograde
After death muscle fibres run out of ATP and calcium begins to leak from te sacroplasmic reticulum into the sacroplasm. This results in a condition known as
Rigor Mortis
A —- is a muscle whose contraction is chiefly responsible for producing a particular movement.
Synergist.
At peak levels of muscle exertion the mitochondria can supply
Only about 1/3 of the energy required by the muscle.
A lever consists of
A rigid structure and a fulcrum.
EPSP’s ( excitatory post synaptic potentials) occur when
Ezra sodium ions enter the cell
During anaerobic glycolysis
All answers are correct
Describe the basic sequence of events that occurs as an action potential arrives at the neuromuscular junction and is transmitted to the muscle cell.
Action potential triggers exocytosis of neuro transmitters in vesicles in axon ending. Acetylcholine binds to receptors Motor and plate increase membrane permeability to sodium. AcetylCoE destroys acetylcholine ensuring that each nerve produces a single twitch. Action potential spreads both ways from end of plate across the entire surface of muscle fibre.
Active neurons need ATP to support which of the following?
All of the answers are correct
Creative phosphate
Acts as an energy reserve in muscle tissue.
Contracting the gastronemius muscles to elevate the body on the toes involves a —- lever.
Second class.
At rest the tropomyosin molecule is held in place by
Troponin molecules
A single contraction relaxation cycle in a muscle fibre produces a —-
Twitch
Decreased blood flow to a muscle could result in all of the following except
An increase in intracellular glycogen
Any stimulus that opens —- ion channel will produce a graded potential
All answers are correct
Clusters of RER and free ribosomes on neurons are called
Nissil bodies
After acetylcholinesterase acts the synaptic terminal
Reabsorbs the choline
Active sites become exposed when calcium ions bind to —
Troponin
Aerobic metabolism normally provides —– percent of the ATP demands of a resting muscle cell.
95
At a — synapse a neurotransmitter is released to stimulate the postsynaptic membrane.
Chemical.
During the recovery period following exercise all of the following are true except
Muscle fibres are unable to contract
A drug that blocks ATP production is is introduced to an isolated axon preparation. The axon is the repeatedly stimulated and recordings are made of the response. What effects would you expect to observe.
Initially normal action potentials shown. After 50,000 to 100,000 action potentials have passed less respond would be indicated from axon until it fails to respond. Cell could not replenish sodium and potassium ion gradients.
A post synaptic neuron will have an EPSP when
Chemically regulated sodium channels are open and sodium is diffusing into the cell
After heavy exercise if energy reserves in a muscle are depleted —– occurs
An oxygen debt
At the normal resting potential of a typical neuron it’s sodium- potassium exchange pump transports
3 intracellular sodium ions for 2 extra cellular potassium ions
A sesamoid bone occasionally found within the lateral head of the gastrocnemius is
The fabella
All of the following originate in the scapula except the
Pectoralis major
An infection by the bacterium clostridium tetani can cause the disease called —-
Tetanus
A fascicle is
A group of muscle fibres that are encased in the perimysium.
Damage to the pectoralis major would interfere with a persons ability to
Adduct the humerus
Because skeletal muscle contractions demand large quantities or ATP skeletal muscles have
Many mitochondria and rich blood supply
Deteriorating changes in the distal segment of an axon as a result of a break between it and a soma is called —– degeneration
Wallerian
An —- can be described as a broad tensions sheet
Aponeurosis
A muscle produces its highest tension when in complete —
Tetanus
During repolarization of a neuron
Potassium ions move out of the cell
A muscle that flexes the spinal column is the
Rectus abdominals
Compounds that alter the rate of neurotransmitter release by the presynaptic neuron or change the postsynaptic cells response to neurotransmitters are called ——
Neuro modulators
A muscle whose name in the suffix glossus would be found within or attached to the
Tongue
Communication between axons and muscle fibres occurs at specialized synapses called —–
Neuromuscular junctions
A shift of the resting transmembrane potential toward 0 mV is called
Depolarization
A weight lifter strains to lift a heavy weight and there is no movement of the persons arms holding on to the weight. This type of contraction is called a —- contraction.
Isometric.
A muscle that dorsiflexes the foot is the
Tibialis anterior
A threshold stimulus is the
Depolarization necessary to cause an action potential.
During abdominal surgery the surgeon makes a cut lateral to the linea alba. The muscles that would be cut is the
Rectus abdominius
A muscle that assists the muscle that is primarily responsible for a given action is a —
Synergist
Cholinergic synapses release neurotransmitters
Acetylcholine
A muscle producing tension that peaks and falls at intermediate stimulus rates is said to be in
Incomplete tetanus
At each End of the muscle the collagen fibres of the epimysium and each perimysium and endomysium come together to form a
Tendon.
A muscle that inserts on the body of the mandible is probably involved in
Chewing
A single motor neuron together with all the muscle fibres it innervates is called
A motor unit
A neuron that receives neurotransmitter from another neuron is called
The post synaptic neuron
Axons terminate in a series of fine extensions known as
Telodendria
Adrenergic synapses release the neurotransmitter
Norepinephrine
All of the following are innervated by the facial nerve except for the — muscle
Levator palpebrae superiosis
A movement charges in response to a potential difference is called a
Current
After a stroke what type of glial cell accumulates within the affected brain region?
Microglia
A resting muscle generates most of its ATP by
Aerobic metabolism of fatty acids
Active site o the actin become available for binding after
Calcium bonds to troponin
Deep muscles are called
Profundus
An antagonist to the gastronemius is the
Tibialis anterior
A —- is a rigid structure that moves Ina fixed point
Lever
During the Cori cycle in the liver
Glucose is produced from lactic acid.
Cerebrospinal fluid
is secreted by ependymal cells
A tract of white matter that connects the hippocampus with the hypothalamus is the
fornix.
A patient develops a tumor of a cranial nerve that leads to difficulty in speaking from a loss of tongue movement. Which cranial nerve is affected?
hypoglossal
Divisions of the cerebral hemispheres that are named after the overlying skull bones are
lobes.
A(n) ________ reflex has at least one interneuron placed between the sensory and motor neurons.
polysynaptic
A viral disease that destroys the cells of the anterior gray horn will
lead to skeletal muscle weakness or paralysis.
Cortical regions that interpret sensory information or coordinate motor responses are called ________ areas.
association
All of the following are true of neural reflexes, except that they
cannot be modified by the brain.
Damage to the superior colliculi would interfere with the reflex ability to
react to a bright light.
During embryonic development, which of the following secondary brain vesicles will form the cerebrum?
telencephalon
Cortical regions that interpret sensory information or coordinate motor responses are called ________ areas.
association
Cerebrospinal fluid flows within the
subarachnoid space.
At the optic chiasm
axons from the nasal halves of each retina cross.
Chambers within the brain that contain cerebrospinal fluid are called ______.
ventricles
Cerebrospinal fluid enters the subarachnoid space through the
lateral and median apertures.
Axons crossing from one side of the spinal cord to the other within the gray matter are found in the
gray commissures.
A(n) ________ is a printed record of the brain’s electrical activity over a period of time.
electroencephalogram
Blood vessels traveling within the ________ space deliver oxygen and nutrients to the spinal cord.
subarachnoid
A reflex that is used to assess the sensory function of the trigeminal nerve is the ________ reflex.
corneal
Blood vessels that supply the spinal cord run along the surface of the
pia mater.
A complex, interwoven network of nerves is called a(n) ________.
plexus
A patient develops a clot that blocks the blood supply to the right cerebral hemisphere. What signs and symptoms would you expect as a result of this blockage?
Because the right primary motor cortex controls the muscles of the left side of the body, you would expect left-sided paralysis whose extent and severity will depend on the extent of brain injury. Similarly, the patient will experience somatic sensory loss on the left side of the body. Higher-order functions such as memory, planning, spatial orientation, and emotional control could be damaged but many language skills would be spared.
As you ascend from the medulla oblongata to the cerebrum, the functions of each successive level become
more complex.
Cerebrospinal fluid enters the blood circulation at the
arachnoid granulations.
A neural cortex is found on the surface of the
cerebrum.
Damage to the substantia nigra causes a decrease in the neurotransmitter dopamine. This causes a gradual, generalized increase in muscle tone, which is the main symptom of
Parkinson’s disease.
After suffering a stroke, Mary finds that she cannot move her right arm. This would suggest that the stroke damage is in the area of the ________ lobe.
left frontal
Bob is struck on the left side of the head and is knocked unconscious. When he recovers consciousness, he can hear individual words but cannot understand the meaning of phrases or sentences. This implies damage to his
general interpretive area.
Bill contracts a viral disease that destroys cells in the posterior gray horns in his spinal cord. As a result, which of the following would you expect?
loss of sensation in his torso
As CSF circulates, ________ between it and the interstitial fluid of the CNS is unrestricted between and across the ependyma.
diffusion
Each lateral ventricle communicates with the third ventricle through a(n)
interventricular foramen.
Damage to the premotor cortex of the frontal lobe would interfere with the ability to
play the piano.
Damage to the corpora quadrigemina would interfere with
visual and auditory reflex movements of the head and neck.
Autonomic centers that control blood pressure, heart rate, and digestion are located in the
medulla oblongata.
All of the following are true of polysynaptic reflexes, except that they
are arranged according to dermatomes.
A person with a damaged visual association area may be
able to see letters but unable to associate them into words.
After suffering a blow to the back of the head, Phil loses his vision. The blow probably caused damage to the
occipital lobe.
Damage to the pyramidal cells of the cerebral cortex would directly affect
voluntary motor activity.
During the procedure known as a(n) ________, a needle is inserted into the subarachnoid space in the inferior lumbar region.
lumbar puncture (or spinal tap)
Difficulties in estimating temporal relationships between events may stem from damage to
the prefrontal cortex.
A person who has difficulty comprehending and using written language suffers from the disorder known as ________.
dyslexia
Bell’s palsy is caused by inflammation of the facial nerve (VII). What signs and symptoms would you expect in this condition? Is it permanent?
Patients suffering from Bell’s palsy usually experience paralysis of the facial muscles on the affected side along with a loss of sensation from the anterior two-thirds of the tongue. Pain is rare and the condition usually resolves without specific treatment.
Droopy eyelids and double vision can result from injury to the ________ nerve.
oculomotor
All of the following are true of muscle spindles, except that they
are found in tendons.
Difficulty in swallowing may be a sign of damage to which cranial nerve(s)?
glossopharyngeal and vagus
Cardiovascular centers located in the ________ adjust the heart rate, the strength of cardiac contractions, and the flow of blood through the peripheral tissues.
medulla oblongata
A dorsal and ventral root of each spinal segment unite to form a
spinal nerve.
As the ________ nerve approaches the knee, it divides into two branches, the fibular nerve and the tibial nerve.
sciatic
After age ________ the vertebral column continues to elongate, but the spinal cord itself does not.
4
Damage to the preoptic area of the hypothalamus leads to which problem?
reduced ability to regulate body temperature
A(n) ________ is a depolarization of a sensory dendrite that can lead to an afferent nerve impulse if strong enough.
generator potential
Axons of the corticobulbar tract terminate in the
motor nuclei of cranial nerves.
A sensory receptor characterized peripherally as a free nerve ending and centrally uses glutamate and/or substance P as neurotransmitters, would most likely be a
nociceptor.
Clusters of ganglionic sympathetic neurons lying along either side of the spinal cord are called sympathetic ________ ganglia.
chain
An inhaler used to treat airway constriction in asthma or allergy might contain a drug that
activates 2 adrenergic receptors.
A reduction in sensitivity in the presence of a constant stimulus is referred to as ________.
adaptation
A neuron with nicotinic receptors is exposed to acetylcholine. This will lead to
All of the answers are correct.
All of the following are true of a prickling pain sensation, except that they
are fast adapting.
After arousal by a sensory stimulus, consciousness can be maintained by positive feedback, because of activity in the
All of the answers are correct.
Almost 75 percent of all parasympathetic outflow travels along the
vagus nerves.
Changes in the central nervous system that accompany aging include
All of the answers are correct.
Damage to the ventral roots of the first five thoracic spinal nerves on the right side of the body would interfere with the ability to
dilate the right pupil.
Complex motor activities such as riding a bicycle
require the coordinated activity of several regions of the brain.
As the result of an accident, the white rami of spinal nerves T1 and T2 on the left side of Brad’s body are severed. What organ(s) would you expect might be affected by this injury?
left pupil and the heart
Ascending tracts in the spinal cord relay ________ information.
sensory
Autonomic tone is an important aspect of ANS function because it
allows ANS neurons to increase or decrease their activity, providing a range of control options.
An age-related decline in mental function characterized by difficulties with spatial orientation, memory, language, and personality is called
senile dementia.
A certain drug decreases heart rate by blocking a receptor on cardiac pacemaker cells. This drug probably binds to ________ receptors.
beta-1 adrenergic
Damage to the tectospinal tracts would interfere with the
ability to make reflex responses of the head and neck in response to sudden movements or loud noises.
Conversion of a short-term memory to a long-term memory is called
memory consolidation.
Alzheimer disease is characterized by all of the following, except that it
has a clear genetic basis.
Descending tracts in the spinal cord relay ________ information.
motor
A brain injury to a patient results in facial paralysis. Which descending tract is most likely affected?
corticobulbar tract
A receptor that contains many mechanically-gated ion channels would function best as a
tactile receptor.
A decrease in the autonomic tone of the smooth muscle in a blood vessel would result in
an increase in blood flow through the vessel.
A state of unconsciousness in which an individual cannot be aroused even by strong stimuli is
coma.
A highly sensitive tactile receptor composed of dendritic processes of a single myelinated fiber that makes contact with specialized cells of the stratum germinativum is a
tactile (Merkel) disc
A fast-adapting mechanoreceptor in the papillary layer of the dermis that responds to fine touch is a
tactile (Meissner) corpuscle.
A doctor places drops in the eyes to dilate the pupils for an examination. The type of drug that is used is a(n) ________ drug.
1, 2, and 3
A person is confronted by a dangerous dog. His heart begins to race and beat strongly, his pupils dilate, and his hairs stand up. These signs are the result of
the “fight or flight” response.
A labeled line is
a link between a receptor and a cortical neuron.
Bladder fullness is to ________ as blood pH is to ________.
baroreceptors; chemoreceptors
A tactile receptor composed of highly coiled dendrites that are surrounded by modified Schwann cells and a fibrous capsule is a
tactile (Meissner) corpuscle.
Damage to the pyramidal cells of the cerebral cortex would directly affect
voluntary motor activity.
A visceral motor neuron whose cell body is within the CNS is called a(n)________ neuron.
preganglionic
A receptor potential may
All of the answers are correct.
Based on stimulation studies, the “headquarters” of the reticular activating system appears to be based in the
midbrain.
Axons that decussate between the pyramids of the medulla oblongata belong to the ________ tracts.
lateral corticospinal
Based on the motor homunculus, which of the following body regions has the largest motor units?
back
A very large, fast-adapting tactile receptor that is composed of a single dendrite enclosed by concentric layers of collagen is a
lamellated corpuscle.
Chemoreceptors are located in all of the following, except
in the skin.
Control of the diameter of the respiratory passages depends upon
both parasympathetic and sympathetic levels of stimulation.
The ________ tract provides subconscious regulation of balance and muscle tone and is part of the ________ pathway.
vestibulospinal; medial
Central adaptation refers to
inhibition of nuclei located along a sensory pathway.
Collateral ganglia contain neurons that innervate tissues and organs in which cavity?
abdominopelvic
Descending (motor) pathways always involve at least ________ motor neuron(s).
two
A state of unconsciousness in which an individual can be aroused by normal stimuli is
sleep.
Clusters of ganglionic sympathetic neurons that innervate organs in the abdominopelvic region are called ________ ganglia.
collateral
Craniosacral division is another name for the
parasympathetic division of the ANS.
A fast-adapting tactile receptor that monitors movements across the body surface is a
root hair plexus.
A typical gustatory cell survives for only about ________ days before it is replace
10
Abnormal jumpy eye movements that may appear after brain stem or inner ear damage are called ________.
nystagmus
A(n) ________ is an infection in one of the glands on the eyelids.
sty or chalazion
All of the following are true of olfactory pathways, except
they project first to the mamillary bodies and then to the thalamus.
Gustatory receptors are located
on the surface of the tongue.
A pigment synthesized from vitamin A is
retinal.
All of the following are true of the fibrous tunic of the eye, except that it
produces aqueous humor.
A sound with a frequency of 12,000 hertz would
be high-pitched.
A structure that is located at the medial canthus and contains glands that contribute to a gritty deposit is the
lacrimal caruncle.
A patient who experienced head trauma has lost the ability to taste spicy food. You should expect damage to cranial nerve ________.
V
During accommodation, the ciliary muscle ________ and the suspensory ligaments become ________ which, in turn, cause the lens to become ________.
contracts; loose; round
Each gustatory cell extends ________ (or taste hairs) into the surrounding fluids through a narrow taste pore.
microvilli
An area of the retina that contains only cones and is the site of sharpest vision is the
fovea.
How would a molecule that mimics cAMP affect an olfactory receptor?
All of the answers are correct.
An irregularity in curvature in the cornea or lens called a(n) ________ causes a reduction in visual acuity.
astigmatism
A person suffering from ________ can see objects that are close, but distant objects appear blurred.
myopia
If your vision is 20/15, this means that you can
see objects at 20 feet that individuals with normal eyesight can see at 15 feet.
Amacrine and ________ cells facilitate or inhibit communication between photoreceptors and ganglion cells.
horizontal
A person suffering from ________ can see distant objects more clearly than those that are close.
hyperopia
Having to adjust to a dark room after walking in from bright light is because
rods exposed to strong light need time to regenerate rhodopsin.
An elongate outer segment containing membranous discs and a narrow connecting stalk that attaches the outer segment to the inner segment describes
a photoreceptor.
Each of the special senses can be expected to decline in some way over time. Describe some of the changes commonly seen in the function of the special senses with age.
Olfactory receptors are reduced in number and olfactory glands decline in activity. Both changes reduce olfactory acuity. Gustatory sense declines with a decline in the number of taste buds and taste receptors. Vision suffers from a loss of retinal function, clouding of lens and cornea, and loss of lens elasticity, leading to senile hyperopia (presbyopia). Hearing declines due to accumulation of cerumen, scarring of the tympanum, arthritis of the ossicular chain, and loss of proximal hair cells in the organ of Corti, leading to high-tone deafness. Balance declines due to nerve problems, fluid problems, and vascular problems, leading to faulty or delayed vestibular information. That decline coupled with a sluggish and weak motor response increases the risk of falls and consequent trauma.
A ray of light entering the eye will encounter these structures in which order?
conjunctiva cornea aqueous humor lens vitreous body retina choroid
During accommodation, the ciliary muscle ________ causing the ciliary body to move ________ and apply ________ tension on the lens.
contracts; forward; less
All of the following are true of the lacrimal glands, except that they
produce a strongly hypertonic fluid.
An infection that damages the vestibular nerve could result in a loss of
equilibrium.
Gustatory receptors are clustered in individual ________.
taste buds
How would blockage of the auditory (Eustachian) tube at its exit in the nasopharynx by lymphatic tissue (“adenoids”) affect ear function and health?
Blockage of the auditory tube leads to pain because pressure cannot equilibrate between the middle ear and the atmosphere. Also, fluid can accumulate (otitis media) in the middle ear, which is also painful and potentially infective. Untreated, adenoids can lead to scarring of the tympanum and some loss of hearing.
A sty ________
All of the answers are correct.
Before an olfactory receptor can detect an odorant, it has to
bind to receptors in olfactory cilia.
A(n) ________ is a basic unit or packet of light energy.
photon
A loud noise causes
All of the answers are correct.
Gravity and linear acceleration are sensed in the
saccule and utricle.
An adult has approximately ________ taste buds.
3,000
A sudden increase of light into the eye would cause
contraction of the sphincter pupillary muscles.
What is the function of rods?
Rod cells, or rods, are photoreceptor cells in the retina of the eye that can function in less intense light than the other type of visual photoreceptor, cone cells. Rods are concentrated at the outer edges of the retina and are used in peripheral vision.
A type of farsightedness that results from a loss of lens elasticity with age is ________.
presbyopia
A normal, relaxed inhalation carries about ________ of the inhaled air to the olfactory organs.
2 percent
Bowman glands, also known as the ________ glands, secrete a thick, pigmented mucus that absorbs water.
olfactory
