What are the major chemical components of the cell membranes?
Ans: Lipids and Proteins
Explanation: The major chemical components of all cell membranes are lipids and proteins, but the percentage of each varies among different membranes.
What organic compound facilitates transportation across cell membranes by acting as receptors, transport channels for electrolytes & enzymes to drive active pumps?
Ans: Proteins
Explanation: Proteins act a (1) recognition & binding units (receptors) for substances moving in & out of the cell; (2)pores or transport channels for various electrically charged particles called ions or electrolytes & specific carriers for
What prevents water-soluble molecules from entering cells across the plasma membrane?
Ans: Phospholipid bilayer
Exp: The bilayer's structure accounts for one of the essential functions of the plasma membrane-it is impermeable to most water-soluble molecules b/c they are insoluble in the oily core region. The bilayer serves as a barrier to
Using the fluid mosaic model, a cell is actively capable of protecting itself against injurious agents by:
Ans: altering the number & patterns of receptors to bacteria, antibodies & chemicals
Exp: Hormones, bacteria, viruses, drugs, antibodies, chemicals that transmit nerve impulses, & other substances attach to the plasma membrane by means of receptor molecul
Which form of cell communication is used to communicate within the cell itself & with other cells in direct physical contact?
Ans: Plasma membrane-bound signaling molecules (involving receptors)
Exp: Cells communicate in 3 ways: (1) they form protein channels (gap junctions) that directly coordinate the activities of adjacent cells; (2) they display plasma membrane-bound signali
Which mode of chemical signaling uses blood to transport communication to cells some distance away?
Ans: Hormone Signaling
Exp: It involves specialized endocrine cells that secrete hormone chemicals (e.g. thyroid-stimulating hormone) released by one set of cells & travel though the tissue & through the bloodstream to produce a response in other sets of
Which mode of chemical signaling uses local chemical mediators that are quickly taken up, destroyed or immobilized?
Ans: Paracrine Signaling
Exp: In paracrine signaling, cells secrete local chemical mediators that are quickly taken up, destroyed, or immobilized
Neurotransmitters affect the postsynaptic membrane by binding to:
Ans: Receptors
Exp: In each type of chemical signaling, the target cell receives the signal by first attaching to is receptors
How do cells receive communication from the extracellular fluid surrounding them?
Ans: Chemical messengers such as ligands
Exp: Channel opening & closing can be initiated in 1 of 3 ways: (1) by binding a ligand to a specific membrane receptor that is closely associated w/ the channel (G-proteins); (2) by changes in electric current in
The mammary glands enlarge during pregnancy primarily as a consequence of:
Ans: Hormonal Hyperplasia
Exp: Hormonal occurs chiefly in estrogen dependent organs, such as the uterus & breast
What is a consequence of leakage of lysosomal enzymes during chemical injury?
Ans: Enzymatic digestion of the nucleus & nucleolus occurs, halting DNA synthesis
Exp: Enzymatic digestion of cellular organelles, including the nucleus & nucleolus, ensures, halting synthesis of DNA & ribonucleic acid (RNA)
What organs are affected by the type of necrosis that results from hypoxia caused by severe ischemia or caused by chemical injury?
Ans: Kidneys and heart
Exp: Coagulative necrosis, which occurs primarily in the kidneys, heart & adrenal glands, commonly results from hypoxia caused by severe ischemia or hypoxia caused by chemical injury, especially ingestion of mercuric chloride
What effect does fetal alcohol syndrome (FAS) have on infants?
Ans: Cognitive impairment & facial anomalies
Exp: FAS can lead to growth restriction, cognitive impairment, facial anomalies, & ocular disturbances
What physiologic changes occur during heath exhaustion?
Ans: Hemoconcentration occurs because of the loss of salt & water.
Exp: Heat exhaustion occurs when sufficient salt & water loss results in hemoconcentration.
What is the common site of lipid accumulation?
Ans: Liver
Exp: Although lipids sometimes accumulate in heart & kidney cells, the most common site of intracellular lipid accumulation or fatty change, is liver cells.
Which of the following transmit a never impulse at the highest rate?
Ans: Large myelinated axons
Exp: If the myelin layer is tightly wrapped many times around the axon forming nodes of Ranvier, it increases conduction velocity & the neuron is referred to as myelinated. Larger myelinated axons transmit impulses at a faster
The ___ is the membrane that separates the cerebellum from the cerebrum.
Ans: tentorium cerebelli
Exp: The tentorium cerebelli is a membrane that separates the cerebellum below from the cerebral structures above. The remaining options do not perform the function described in the stem
Where is the neurotransmitter norepinephrine secreted?
Ans: In the sympathetic postganglion
Exp: Most postganglionic sympathetic fiber release norepinephrine (adrenaline). The remaining options do not reflect the correct site of norepinephrine secretion.
Which nerves are capable of regeneration?
Ans: Myelinated nerves in the peripheral nervous system
Exp: Nerve regeneration is limited to myelinated fibers & generally only in the PNS.
The ability of the eyes to track moving objects through a visual field is primarily a function of the ___ colliculi
* voluntary & involuntary visual motor movements (e.g. the ability of the eyes to track moving objects in the visual field
Ans: Superior
Exp: The superior colliculi are involved w/ voluntary & involuntary visual motor movements (e.g. the ability of the eyes to track moving objects in the visual field). This is not the primary function of the remaining options.
What parts of the brain mediate the expression of affect, both emotional & behavioral states?
Ans: Limbic system & prefrontal cortex
Exp: Expression of affect (emotional & behavioral states) is mediated by extensive connections w/ the limbic system & prefrontal cortex. The remaining options are not involve in these expressions
Pricking one's finger w/ a needle would cause minimal pain, whereas cutting one's finger w/ a knife would produce more pain. This is an example of the ___ theory of pain
Ans: Specificity
Exp: According to the specificity theory, there is a direct relationship between the intensity of pain & the extent of tissue injury> The remaining options are not related to the intensity of perceived pain>
The ___ theory proposes that pain results from excessive stimulation of sensory receptors.
Ans: Intensity
Exp: Rene Descartes proposed that the body works like a machine that can be studied by scientific methods & that injury activates specific pain receptors & fibers that project to the brain. He further postulated that the intensity of pain i
What type of nerve fibers transmit pain impulses?
Ans: A-delta fibers
Exp: These two receptors are associated w/ lightly myelinated, medium-sized A-delta (Ad) fibers. Other types of mechanical, thermal & chemical nociception are transmitted by excitation of polymodal nociceptors and & are carried on smal
Where do primary efferent pain fibers enter the spinal cord?
Ans: Dorsal root ganglia
Exp: The cell bodies of primary-order neurons or pain-transmitting neurons reside in the dorsal root ganglia just lateral to the spine along the sensory pathways the penetrate the posterior part of the cord
Where is the gate located that is referred to in the gate control theory of pain?
Ans: Substantia gelantinosa
Exp: The synaptic connections between cells of primary & secondary order neurons located in the substantia geliatinosa & other rexed laminae function as a "pain gate". The remaining options do not act in the function.
Which spinal tract carries the most nociceptive information?
Ans: Lateral Spinothalamic tract
Exp: Most nociceptive information travels by means of ascending columns in the lateral spinothalamic tract (also called the anterolateral funiculus.)
Where is the major relay station of sensory information?
Ans:Thalamus
Exp: Although the organization of all the ascending tracts is complex, the principal target for nociceptive afferents is the thalamus (major relay station of sensory information in general.) The remain options do not fulfill this objective-ba
Where in the central nervous system does pain perception occur?
Ans: Parietal
Exp: On the postcentral gyrus of the parietal lobe is topographically organized representation of the body that mirrors the concentration of peripheral sensory receptors known as the sensory homunculus. This area of the brain is thought to b
Massage therapy relieves pain by stiumalting the ___ that close the pain gate.
Ans: A-beta fibers
Exp: Afferent A-beta (Ab) fibers carry non-noxious low-threshold mechanical information gained by touch, vibration, & pressure
What part of the brain provides the emotional response to pain?
Ans: Limbic System
Exp: The limbic & reticular tracts are involved in alerting the body to danger, initiating arousal of the organism, & emotionally processing the perceived afferents signals not just as stimuli, but as pain
Which neurotransmitters inhibit pain in the medulla & pons?
Ans: Norepinephrine & serotonin
Exp: Norepinephrine & 5-hydroxytryptamine (serotonin) contribute to pain modulation (inhibition) in the medulla & pons.
Which endogenous opioid is located in the hypothalamus & pituitary & is a strong mu-receptor?
Ans: Endorphins
Exp: Endorphins were first discovered in the human PAG in 1979, b-endorphin being the best studied of the group. The synthesis & activity of b-endorphin are concentrated in the hypothalamus & pituitary gland
What are the characteristics if visceral pain?
Ans: It is perceived as poorly localized & is transmitted by the sympathetic nervous system
Exp: Visceral pain refers to pain in the internal organs & the abdomen & is transmitted by sympathetic afferents. It is poorly localized b/c of fewer nociceptors i
How do enkephalins & endorphins act to relieve pain?
Ans:
Exp: These substances are neurohormones that act as neurotransmitters by binding to one or more G protein-coupled opioid receptors.
Release (increase) of epinephrine increases body temperature by increasing?
Ans: heat production
Exp: Epinephrine and norepinephrine produce a rapid transient increase in heat production by raising the body's basal metabolic rate
Using a fan to reduce body temperature is an example of which mechanism of heat loss?
Ans: Convection
Exp: Convection is the transfer of heat through currents of gases or liquids
Heat loss from the body via convection occurs by:
Ans: transfer of heat through currents of liquids or gas
Exp: Convection is the transfer of heat through currents of gases and liquids
Which disorder of temperature regulation is caused by prolonged high environmental temperatures that produce dehydration, decreased plasma volumes, hypotension, decreased cardiac output & tachycardia?
Ans: Heat Exhaustion
Exp: heat exhaustion, or collapse, is a result of prolonged high core or environmental temperatures resulting in dehydration, decreased plasma volumes, hypotension, decreased cardiac output & tachycardia.
Children are more susceptible to heat stroke than are adults because:
Ans: Children are more susceptible to heat stroke than are adults because (1) they produce more metabolic heat when exercising; (2) they have a greater surface area-to-mass ration & (3) their sweating capacity is less than that of adults
In acute hypothermia, what physiologic change shunts blood away from the colder skin to the body core in an effort to decrease heat loss?
Ans: Peripheral vasoconstriction
ExP: Tissue hypothermia slows the rate of chemical reactions (tissue metabolism), increases the viscosity of the blood, slows blood flow through the microcirculation, facilitates blood coagulation, & stimulates profound va
A medication used to reverse effects of malignant hyperthermia is:
Ans: Dantrolene Sodium
Exp:Treatment includes withdrawal of the provoking agents & administration of dantrolene sodium (a skeletal relaxant that inhibits calcium release during muscle contraction). The other options are not effective in the treatment of m
What are expected changes in sleep patterns of older adults?
Ans: They experience frequent awakenings during the night with less time spent in stage IV sleep.
Exp: The sleep pattern of the older adult includes total decreased sleep time & takes longer to fall asleep. Older adults tend to go to sleep earlier in the
Open-angle glaucoma occurs because of ___ humor
Ans: Obstructed outflow of aqueous humor
Exp: Open-angle glaucoma is characterized by intraocular pressures above the normal pressures of 12 to 20 mmHg maintained by the inadequate outflow of aqueous fluid
How dos glaucoma cause blindness?
Ans: By pressure on the optic nerve
Exp: Loss of visual acuity results from pressure on the optic nerve
A sensorineural hearing loss may be a result of:
Ans: Meniere dieses, aging, diabetes mellitus & noise exposure all apply.
Exp: A sensorineural hearing loss is caused by impairment of the organ of Corti or its central connections. The hearing loss may be gradual or sudden. Conditions that commonly cause
Define Scotoma
Ans: Defect in central field
ExP: a scotoma is a circumscribed defect of the central field of vision
Define Nystagmus
Ans: Involuntary movement of eyeballs
Exp: Nystagmus is an involuntary unilateral or bilateral rhythmic movement of the eyes
Define Hemianopia
Ans: Defective vision in half of a visual field
Exp: Hemianopia describe defective vision in half of a visual field
Define Anosmia
Ans: Loss of ability to smell
Exp: Anosmia is the complete loss of smell
Define Parageusia
Ans: Perversion of sense of taste
Exp: Parageusia is a perversion of taste in which substances possess an unpleasant flavor
What causes stage 1 of intracranial hypertension? Stage 1 intracranial hypertension is caused by the:
Ans: Displacement of cerebrospinal fluid (CSF) followed by compression of the cerebral venous system
Exp: If intracranial pressure remains high after CSF displacement out of the cranial vault, cerebral blood volume is altered, which causes state 1 intracr
Dilated & sluggish pupils, widening pulse pressure & bradycardia are clinical findings evident of which stage of intracranial hypertension?
Ans: Stage 3
Exp: Stage 2 of intracranial hypertension presents clinical manifestations that include decreasing levels of arousal, Cheyne-Stokes respiration or central neurogenic hyperventilation, pupils that become sluggish & dilated, widened pulse press
Dilation of the ipsilateral pupil following uncial herniation is the result of pressure on which of the following cranial nerves?
Ans: Oculomotor (CN III)
Exp: The oculomotor cranial nerve (CN III) is involved in this manifestation of pupil dilation
Which of the following is the most critical index of nervous system dysfunction?
Ans: Level of consciousness
Exp: Level of consciousness is the most critical clinical index of nervous system function or dysfunction. An alteration in consciousness indicates either improvement or deterioration of a person's condition
Diagnostic criteria for a vegetative state (VS) include:
Ans: Return of autonomic functions such as gastrointestinal function
Exp: Diagnostic criteria for VA includes return of so-called vegetative (autonomic) functions, including sleep-wake cycles & normalization of respiratory & digestive system functions
Uncal herniation occurs when:
Ans: The hippocampal gyrus shifts from the middle fossa through the tentorial notch into the posterior fossa
Exp: Uncal herniation (hippocampal herniation, lateral mass herniation) occurs when the uncus or hippocampal gyrus (or both) shifts from the middl
Which assessment finding marks the end of spinal shock?
Ans: Spinal reflexes gradually return
Exp: A gradual return of spinal reflexes marks the end of spinal shock
In amyotrophy, paresis & paralysis are segmental. Why is the segmental character of weakness difficult to recognize? The weakness resulting from the segmental paresis & paralysis characteristic of amyotrophy is difficult to recognized because:
Ans: Each muscle is supplied by 2 or more nerve rods
Exp: The paresis & paralysis associated w/ anterior horn cell injury are segmental, but because each muscle is supplied by two or more roots, the segmental character of the weakness may be difficult to
Clinical manifestations of Parkinson disease are cause by a deficit in which neurotransmitter?
Ans: Dopamine
Exp: Parkinson disease is a commonly occurring degenerative disorder involving deficits of dopamine
What pathologic alteration produces tremors at rest, rigidity akinesia, & postural abnormalities?
Ans: Atrophy of neurons in the substantia nigra that produce dopamine
Exp: The hallmark characteristics of Parkinson disease are a result of a loss of dopaminergic pigmented neurons in the substantia nigra (SN) pars compacta w/ dopaminergic deficiency in
Define Expressive Dysphasia
Ans: Broca dysphasia
Exp: Broca dysphasia is an expressive dysphasia of speech & writing but with retention of comprehension
Define Receptive Dysphasia
Ans: Wernicke aphasia
Exp: Wernicke dysphasia is a disturbance in understanding all language-verbal & reading comprehension
Describe decrease in voluntary movement
Ans: Akinesia
Exp: Akinesia is an absence, poverty, or lack of control of associated & voluntary muscle movements. There is a disturbance in time it takes to perform a movement
Describe abnormal involuntary movement
Ans: Paroxysmal dyskinesia
Exp: Paroxysmal dyskinesias are abnormal, involuntary movements that occur as spasmas
Describe lower motor neuron disorders
Ans: Flaccidity
Exp: Lower motor neuron syndromes manifest with impaired voluntary & involuntary movements (i.e. hypotonia)
Describe upper motor neuron disorders
Ans: Spasticity
Exp: An upper motor neuron syndrom is characterized by paresis or paralysis, hypertonia (spasticity), & hyperreflexia
What complication is occurring for a person who has a spinal cord injury above T6 & is experiencing paroxysmal hypertension as well as piloerection & sweating above the spinal cord lesion?
Ans: Autonomic hyperreflexia
Exp: Individuals most likely to be affected have lesions at the T6 level or above. Autonomic hyperreflexia is characterized by paroxysmal hypertension (up to 300 mmHg systolic), a pounding headache, blurred vision, sweating ab
Why does a person who has a spinal cord injury experience faulty control of sweating?
Ans: The hypothalamus is unable to regulate body heat as a result of sympathetic nervous system damage.
Exp: The condition also results in disturbed thermal control b/c the hypothalamus is unable to regulate a damaged sympathetic nervous system. This dama
Multiple sclerosis & Guillain-Barre syndrome (GBS) are similar in that they both?
Ans: Result from demyelination by an immune reaction
Exp: The condition also results in disturbed thermal control b/c the hypothalamus is unable to regulate a damaged sympathetic nervous system. This damage causes faulty control of sweating & radiation th
What sequence causes autonomic hyperreflexia-induce bradycaria?
Ans: Stimulation of the carotid sinus to the vagus nerve to the SA node.
Exp: The intact autonomic nervous system reflexively responds w/ an arteriolar spasm that increases blood pressure. Baroreceptors in the cerebral vessels, the carotid sinus, & the ao
Of the following people, who is at the highest risk for a cerebrovascular accident (CVA)?
Ans: Black women older than 70 years age
Exp: 50% of CVAs occur in persons older than 70 years. Strokes, however, do occur in a 3:10 ration (28%) in individuals younger than 65 years. Stroke tends to run in families. The incidence of stroke 2.5x higher in
A right hemisphere emoblic cerebrovascular accident has resulted in left-sided paralysis & reduced sensation of the left foot & leg. The vessel most likely affected by the emobli is the right ___artery.
Ans: Anterior cerebral
Exp: Symptomatology of an embolic stroke in the right anterior cerebral artery would include left-sided contralateral paralysis or paresis (greater in foot and thigh) and mild upper extremity weakness with mild contralateral lower e
A man was in an automobile accident in which his forehead struck the windshield. A blunt force injury to the forehead would result in a coup injury to the ___region.
Ans: Frontal
Exp: The focal injury may be coup (directly below the point of impact). Objects striking the front of the head usually produce only coup injuries (contusions and fractures) because the inner skull in the occipital area is smooth.
A blunt force injury to the forehead would result in a countercoup injury to the ___ region.
Ans: Occipital
Exp: The focal injury may be coup (directly below the point of impact) or contrecoup (on the pole opposite the site of impact). Objects striking the back of the head usually result in both coup and contrecoup injuries because of the irregul
The most likely rationale for body temperature fluctuations after cervical spinal cord injury is that the person:
Ans: Has sympathetic nervous system damage resulting in disturbed thermal control
Exp: The condition in disturbed thermal control b/c the sympathetic nervous system is damaged
A man who sustained a cervical spinal cord injury 2 days ago suddenly develops severe hypertension & bradycardia. He reports severe head pain & blurred vision. The most likely explanation for these clinical manifestations is that he is:
Ans: Developing autonomic hyppereflexia
Exp: Autonomic hyperreflexia is characterized by paroxysmal hypertension (up to 300 mm Hg systolic), a pounding headache, blurred vision, sweating above the level of the lesion with flushing of the skin, nasal conge