Test Questions Version 2 Flashcards
Maintaining homeostasis is necessary for proper health. Appropriate amounts of fluid and electrolytes are essential. In our case studies about the med student and the earthquake survivor who was trapped for several days, we learned about dehydration. But what about over-hydration? A low sodium concentration in the body (hyponatremia) can be caused by too much water. Which of the following are important roles for sodium in the body?
A. Blood pressure control
B. Fluid balance
C. Neuron function
D. Muscle function
E. All of the above
E
The normal blood sodium level is 135 to 145 mEq/L. Hyponatremia refers to a decrease in serum sodium concentration (< 135 mEq/L milliequivalents/liter) caused by an excess of water relative to solute. A study in The new England Journal of Medicine reported that out of 488 runners who ran The Boston Marathon, thirteen percent had hyponatremia and 0.6 percent had critical hyponatremia (120 mmol per liter or less). When the sodium level in your blood is too low____
A. osmoreceptor cells will sense a change in osmotic pressure
B. extra water goes into your cells and makes them swell, which can be dangerous especially in the brain, since the brain cannot expand past the skull.
C. extra water comes out of your cells and makes them shrink, which can cause your skin to wrinkle
D. Both A and B
E. None of the above
D
Myasthenia gravis is a chronic autoimmune, neuromuscular disease that can cause weakness in the muscles that allow for breathing. In myasthenia gravis, antibodies block receptors for acetylcholine at the neuromuscular junction, which prevents the muscle from contracting (see the figure below). The inability to ventilate adequately due to a neuromuscular disease such as Myasthenia gravis can disrupt homeostasis and can cause ____
A. An increase in blood carbon dioxide
B. Respiratory acidosis
C. An increase in blood pH
D. A and B only
E. A, B and C
D
Postural hypotension (also known as orthostatic hypotension) refers to a drop in blood pressure that happens when a person stands up after sitting or lying down. Which of the following occurs in the process of restoring homeostasis when this happens?
A. When the blood pressure falls, baroreceptors are stretched less
B. Osmoreceptors detect changes in oxygen and H+ levels
C. Due to the low blood pressure, baroreceptors increase their rate of firing action potentials to the cardiac control centers in the midbrain
D. There is an increase in the rate and depth of breathing which results in an increase in plasma CO2 levels
E. None of the above.
A
The American black bear can hibernate for up to 6 months. During this period, they do not eat, drink, urinate, or defecate. They elicit minimal movements and typically do not leave their dens. They can suppress their metabolism to 25% of basal rates and regulate their body temperature from 30-36 degrees Celsius. What are some ways animals can regulate their body temperature (or thermoregulate)?
A. Respond to high temperatures by vasoconstricting surface blood vessels which results in a higher heat transfer from the skin and cools the body down.
B. Transmit action potentials along motor neurons to the smooth muscle surrounding the arterioles in the skin to cause shivering
C. Utilize a counter current mechanism for blood flow in arteries and veins that are adjacent
D. A and C only
E. B and C only
C
Structure (anatomy) and function (physiology) go together! The four basic tissue types are__
A. Endothelial, Cartilage, Nervous, Muscle
B. Endothelial, Nervous, Muscle, Connective
C. Cardiac, Smooth, Skeletal, Epithelial
D. Adipose, Blood, Bone, Cardiac
E. None of the above
E
Glioblastoma is a type of cancer that starts as a growth of cells in the brain or spinal cord. It grows quickly and can invade and destroy healthy tissue. There’s no cure for glioblastoma. Glioblastoma forms from cells called astrocytes. Astrocytes ____
A. are found in the PNS
B. are phagocytic cells that ingest and break down pathogens
C. produce cerebrospinal fluid
D. form myelin sheaths in the CNS
E. None of the above
E
Electrical synapses are also known as gap junctions and are direct points of contact between the cytoplasm of adjacent neurons. Gap junctions represent a low-resistance pathway that allows charged particles and small molecules to flow freely in either direction and couples the electrical activity of adjoining cells. Which of the following is (are) TRUE with regard to electrical synapse?
A. Electrical synapses connect cardiac muscle cells
B. A gap junction is composed of proteins called connexons
C. Electrical synapse transmit signals faster than chemical synapses
D. All of the above (A, B and C)
E. None of the above
D
The equilibrium potential (in mV) across the membrane of a cell for a singly charged positive ion (Eion)_____
A. can be calculated to be about +60mV for potassium
B. can be predicted using the Nerst equation
C. is known as the resting membrane potential
D. can be predicted using the Goldman equation
E. is reached when the distribution of Na+ is 15mM outside the cell, and the distribution of K+ is 5mM inside the cell
B
. In class, we learned about a number of different ion channels and how they are gated (such as voltage gated, ligand gated, mechanically gated, etc.) and what can happen if there is a mutation in them, such as with our case study on Malignant Hyperthermia. Regarding ion channels, which of the following is (are) TRUE statement(s).
A. Calcium ion channels (such as the Ryanodine receptors, RyR) are located on the sarcoplasmic reticulum of skeletal muscle.
B. Nodes of Ranvier have a high density of voltage gated Na+ and K+ channels
C. Ligand gated Ca++ channels are found at the terminal of axons and facilitate the movement and fusion of synaptic vesicles to the plasma membrane for the release of neurotransmitters into the synapse
D. A, B and C are correct
E. Only A and B are true
E
An action potential occurs when the membrane potential of a specific cell rapidly rises and falls. In neurons, action potentials play a central role in cell–cell communication. With regard to action potentials, _____
A. The size of an action potential is related to the intensity of the stimulus or the amount of neurotransmitter released.
B. Axons with a smaller diameter will conduct action potentials faster than larger diameter axons because larger axons have more resistance.
C. Action potentials are conducted in a detrimental fashion, meaning that their magnitude decreases as they spread over the plasma membrane.
D. The size (or magnitude) of an action potential evoked during the relative refractory period can be smaller than normal
E. The conduction velocity of an action potentials is slower when the membrane resistance is greater.
D
In certain diseases, medicines that are used to increase particular neurotransmitters are found to be beneficial. Which neurotransmitters are usually most helpful in the treatment of: Parkinson’s Disease, Alzheimer’s Disease, ADHD, and Depression respectively?
A. Glycine, Enkephalins, Norepinephrine, GABA
B. Morphine, Nitrous Oxide, Dopamine, Glutamate,
C. Dopamine, Acetylcholine, Norepinephrine, Serotonin
D. Acetylcholine, Endorphins, Glycine, Nitrous Oxide
E. None of the above
C
Neurotransmitters can be characterized as excitatory, inhibitory or modulatory. Which of the following is a/are TRUE statement(s) with regard to neurotransmission?
A. IPSP’s can occur when K+ enters the cell
B. A depolarizing graded potential can cause an action potential
C. Temporal summation can be defined as: summation of EPSPs produced by the firing of different presynaptic neurons
D. EPSP’s can occur when Cl- enters the cell
E. Both B and C
B
As animals evolved, there became a greater need for an increasingly complex and adept nervous system. In the 4-week embryo, the brain can be divided into 3 major components. In the 5-week embryo, the brain is even more specialized and can be divided into 5 major components. The adult brain has many specialized regions. Which of the following brain regions in the 5-week embryo correspond correctly with regions in the adult brain?
A. metencephalon: cerebellum and pons
B. diencephalon: medulla oblongata
C. mesencephalon: thalamus
D. forebrain: diencephalon
E. All of the above
A
Meningitis is an infection and inflammation of the fluid and membranes surrounding the brain and spinal cord. A bacterial or viral infection usually causes swelling and can produce headache, fever, and a stiff neck. The cranial meninges ___
A. are comprised of the pia mater, arachnoid mater, and dura mater with the pia mater residing closest to the skull.
B. provide structural support for blood vessels
C. cover the brain but are not found in the spinal cord
D. are composed of endothelial cells and tight junctions
E. None of the above
B
The cerebral spinal fluid (CSF) can be infected in Meningitis and if untreated, Meningitis can be fatal.
The CSF ___
A. can be found in the subarachnoid space
B. is produced by microglial cells
C. is secreted by cells in the reticular formation
D. flows through the corpus callosum to reach both brain hemispheres
E. none of the above
A
Alzheimer’s disease (AD) is the most common type of dementia worldwide. Hippocampal atrophy and ventricular enlargement have been associated with AD. The ventricular system ___
A. are cavities in the brain filled with cerebral spinal fluid.
B. are comprised of four ventricles: two lateral ventricles, the third ventricle, and the fourth ventricle.
C. can help absorb the shock if there is a head injury
D. both A and C
E. A, B and C
E
We used to think of brains as symmetrical, functioning in the same way on the left and right sides, but we now know that this is not so. From the small brains of insects to variously sized brains of vertebrates, including humans, the left and right sides process information differently and control different patterns of behavior. This is known as lateralization. Which of the following are TRUE statements regarding the brain?
A. The left cerebral hemisphere responds to sensory signals from the right side of the body and
controls movements on right side of body. The right hemisphere responds and controls
movement on left side of body.
B. Hemispheres are connected by thick axon bundles (the corpus callosum) which enables the exchange of information between the hemispheres.
C. The right hemisphere functions to focus on details (such as recognizing a particular face in a crowd), spoken and written language, abstract reasoning and math; but not things like music and art.
D. Language areas, such as Wernicke’s and Broca’s areas are found in the right hemisphere.
E. Both A and B
E
If a person suffers a stoke in the parietal lobe, he most likely may have difficulty with ____
A. vision
B. the perception and integration of stimuli from the senses
C. executive function
D. the coordination and refinement of body movements
E. All of the above
B
Which of the following is correctly matched?
A. Produces different levels of alertness or consciousness: Ascending reticular formation
B. Controls body temperature, hunger, thirst: Hypothalamus
C. Coordinates/refines body movements by information integration and comparison: Cerebellum
D. Both B and C
E. A, B and C
E
In our case study on opioids, we learned a great deal about how drugs work on the brain to produce pleasure, tolerance and addiction. Which of the following statements are TRUE?
A. The natural opiates of the body are endorphins and enkephalins
B. Dopamine is a neurotransmitter present in regions of the brain that regulate movement, emotion, motivation, and feelings of pleasure.
C. The Ventral Tegmental Area (VTA) is part of the midbrain and is involved in pleasure pathway/reward circuit.
D. Only A and B
E. A, B and C
E
The most prominent signs and symptoms of Parkinson’s disease occur when the neurons in a particular part of the brain become impaired or die. What is this part of the brain and what does it primarily control?
A. Primary somatosensory area; proprioception
B. Basal ganglia; voluntary movement
C. Thalamus; information relay
D. Hypothalamus; memory and learning
E. Cerebellum; breathing
B
A lobotomy is a type of brain surgery that became popular in the 1930s as a treatment for mental health conditions such a schizophrenia. It involves severing the connection between the frontal lobe and other parts of the brain. Many lobotomized patients exhibited reduced tension and agitation, but many also showed other affects such as apathy, passivity, lack of initiative, poor ability to concentrate, and a generally decreased depth and intensity of emotional response to life. Some died as a result of the procedure. Which of the following is/are a primary function of the frontal lobe?
A. balance and coordination
B. language comprehension
C. executive functions such as decision making, planning etc.
D. blood pressure and heart rate control
E. speaking and swallowing
C
Our nervous systems are highly organized. For example, the autonomic system _____
A. refers to collections of motor neurons (ganglia) situated in the head, neck, thorax, abdomen, and pelvis, and to the axonal connections of these neurons
B. is usually voluntary and controls body movements that are conscious
C. has two divisions, the CNS and the PNS
D. is a subdivision of the afferent system
E. None of the above
A
The sympathetic system is often associated with our “fight or flight” responses. The sympathetic system __
A. is part of the central nervous system
B. often utilizes adrenaline
C. will constrict bronchioles in airways when activated
D. Both A and B
E. None of the above
B
There are 4 types of spinal cord injury: cervical, thoracic, lumbar and sacral. In general, the higher in the spinal column the injury occurs, the more dysfunction a person will experience. Which of the following is TRUE with regard to the spinal cord?
A. It has white matter but no grey matter because it houses axons of nerves and doesn’t have actual neurons
B. The dorsal root transmits efferent information
C. It is a component of the peripheral nervous system
D. All of the above are true
E. None of the above are true
E
Aphasia is the loss of ability to understand or express speech. The most common cause of aphasia is brain damage resulting from a stroke, which is the blockage or rupture of a blood vessels in the brain. Loss of blood in the brain leads to brain cell death or damage. Damage to Broca’s area can lead to Broca’s aphasia, which is characterized by ___
A. difficulty understanding other’s speech
B. fluent language with made up or unnecessary words with little or no meaning
C. difficulty expressing language, hesitant speech
D. unawareness of one’s own mistakes when speaking
E. All of the above
C
Dr. Eric Kandel received the Nobel prize for his research on the physiological basis of memory storage in neurons. What did Dr. Kandel discover?
A. The molecular basis of early LTP involves the insertion of new AMPA receptors in the plasma membrane.
B. In late LTP, a modulatory neurotransmitter (dopamine) is released.
C. New synaptic connections that are more permanent are generated during the formation of short term memory.
D. A and B only
E. A, B and C
D
Spartie is in his apartment and spills some vinegar. He decides to use bleach to clean up the spill resulting in him accidentally producing Chlorine Gas. What type of receptor(s) warned Spartie about the noxious gas he was producing?
A. Mechanoreceptors
B. Chemoreceptors
C. Nociceptors
D. B and C only
E. A, B and C
D
Motion sickness remains a prevalent reminder of the complexity of our balance system. The sensation is generally thought to be due to a sensory mismatch between vestibular, visual and proprioceptive sensory input. With regard to the balance system, which of the following is/are a TRUE statement?
A. Both the vestibular system and the proprioceptive system utilize cation channels.
B. The semicircular canals are filled with endolymph, which is rich in sodium.
C. Both the vestibular system and the proprioceptive system primarily utilize chemoreceptors.
D. The Golgi tendon organ (GTO) in found in the inner ear and detects position and movement by detecting how much and how fast the cupula is displaced.
E. All of the above are true
A
The skin is an organ that forms the outer surface of the body. It shields the body against infection, dehydration, and temperature changes and provides sensory information about the environment. Which of the following sensory receptors are found in the skin and also are correctly matched with their function?
A. Pacinian corpuscle: senses pressure
B. Nociceptors: senses pain
C. Meissners’s corpuscle: senses touch
D. A and C only
E. A, B and C
E
A trapeze is a short horizontal bar hung by ropes from a ceiling support. It is an aerial apparatus commonly used in acrobatic performances. Acrobatic trapeze performers may spin (rotate), swing linearly, and even hang upside down. What part(s) of the vestibular system do performers like this use?
A. Utricle
B. Semicircular canals
C. Saccule
D. A and C only
E. A, B and C
E
Loud noises can damage the hair cells in the inner ear, as well as the auditory nerve. This type of hearing loss is called sensorineural hearing loss, and it is relatively common. Hence it’s important to understand our auditory system. Which of the statements below are TRUE with regard to what occurs when we hear and perceive a sound?
A. Vibrations of pressure (sound waves) travel through the Eustachian tube to the tympanic membrane
B. The eardrum vibrates and the ossicles vibrate
C. Vibration transmitted through the fluid in the scala tympani, which contains endolymph, cause the basilar membrane to vibrate, thereby bending the hair cells against the tectorial membrane and
generating action potentials.
D. None of the above are true. A, B and C are all false.
E. Only A and B are true
B
The unique design of the ear enables us to hear and perceive various sounds. How is this accomplished?
A. Bending steriocilia in one direction on a given hair cell depolarizes the cell and stimulates neurotransmitter release. Bending in the opposite direction repolarizes the cell and stops the release.
B. High pitched sounds (which are comprised of high frequency vibrations) vibrate the basilar membrane at its narrow, stiff beginning end.
C. Action potentials are transmitted by way of the vestibulocochlear nerve to the thalamus, which then sends projections to the auditory cortex in the brain
D. A, B and C are true and are involved in the hearing process
E. None of the above are true
D
Which of the following structures in the eye is/are correctly matched with its description?
A. Ciliary body: part of the eye that includes the ciliary muscle, which controls the shape of the lens, and the ciliary epithelium, which produces the aqueous humor.
B. Anterior chamber: located behind the iris and in front of the lens; filled with vitreous humor
C. Macula: protective outer layer of the eyeball
D. Cornea: vascular layer of the eye
E. All of the above
A
Age-related macular degeneration (AMD) is an eye disease that can blur one’s central vision. It happens when aging causes damage to the macula, the part of the eye that controls sharp, straight-ahead vision. The macula is part of the retina. The retina ___
A. contains rod cells that are hyperpolarized in the dark
B. has regions known as receptive fields and when light hits the center of the receptive field, photoreceptor cells release less glutamate
C. contains bipolar cells that generate and transmit action potentials to the ganglion cells
D. A and B only
E. A, B and C
B
Color vision deficiency (sometimes called color blindness) represents a group of conditions that affect the perception of color. Red-green color vision defects are the most common form of color vision deficiency. Genetic changes involving the OPN1LW or OPN1MW gene cause red-green color vision defects. These changes lead to an absence particular cones or to the production of abnormal opsin pigments in these cones that affect red-green color vision. In the eye, cones ___
A. are numerous in fovea and macula, and aid in visual acuity
B. utilize the photopigment (or photoreceptive molecule): rhodopsin
C. are specialized for detection of low-intensity light
D. are located over most of the retina
E. None of the above
A
Regarding phototransduction, when the receptive field center is in the dark and light is in the surround area, ________
A. Photoreceptor cells, such as rods, are depolarized and they release glutamate constantly
B. Glutamate released from the photoreceptor terminals stimulates ionotropic glutamate receptors on the off-center bipolar cells, Na+ channels are opened, and Na+ flows into the cell.
C. Glutamate released from the photoreceptor terminals stimulates metabotropic glutamate receptors on the on-center bipolar cells, K+ (potassium) channels are opened, there is an efflux of K+, and the on-center bipolar cell is hyperpolarized.
D. Only A and B
E. A, B and C
E
The sense of taste must have carried an evolutionary advantage to have evolved in the first place. Some scientists believe that taste-sensing systems in the mouth perform essential tasks. For example, umami and sweet detection help animals find energy dense nutrients, and bitter detection helps them avoid toxic substances. With regard to taste, which of the following is a TRUE statement?
A. Foliate papillae contain the most sensitive taste buds and decrease in number with age.
B. The perception of taste is influenced by temperature and texture, but not by olfaction.
C. The sour taste sensation is produced by alkaloids.
D. The most sensitive receptors for the bitter taste are found on the tip of the tongue.
E. All of the above are true
A
Anosmia, the loss of smell, is a frequent and often long-term symptom associated with COVID-19. A recent study in the journal: JAMA Neurology, states: “Our findings suggest that SARS-CoV-2 infection of the olfactory epithelium leads to inflammation, which in turn, damages the neurons, reduces the numbers of axons available to send signals to the brain and results in the olfactory bulb becoming dysfunctional.” With regard to olfaction, _____
A. the olfactory tract is a multilayered structure that has axons from olfactory neurons organized into glomeruli
B. each olfactory receptor cell expresses one type of olfactory receptor that can respond to a set of
different odorants.
C. olfactory receptive neurons are known as mitral cells which have dendrites with cilia that protrude into the mucus covering the olfactory epithelium.
D. axons from neurons in the olfactory bulb synapse with neurons in the thalamus which project to olfactory cortex in the frontal lobe of the brain.
E. None of the above are correct statements
B
Which of the following is true when comparing and contrasting the three types of muscle?
A. All three types of muscle can be controlled involuntarily
B. Smooth muscle are usually branched and have multiple nuclei
C. Cardiac muscle is organized into fasciculi
D. Smooth muscle is generally under voluntary control
E. Skeletal muscle is used to regulated blood vessel diameter and change pupil size
A
In a skeletal muscle, the sliding filament contractile mechanism
A. causes thin filaments on each side of a sarcomere to slide over thick filaments towards the center of the A band, bringing the Z lines closer together
B. is inhibited by the influx of Ca2+into the muscle fiber cytosol
C. lengthens the sarcomere to separate the I regions during the contraction phase
D. depends on the stimulation of actin thick filaments until a contraction is completed
E. uses myosin cross bridges to stimulate delivery of Ca2+to the muscle fiber
A
Which of the following is involved in bringing about skeletal muscle relaxation?
A. reuptake of Ca2+ by the sarcoplasmic reticulum
B. action potential ceases
C. removal of acetylcholine at the endplate
D. filaments sliding back to their resting position
E. all of the above
E
Aerobic exercises like walking, running, hiking, swimming, skiing, and dancing are all considered isotonic exercise. So are resistance training exercises that involve movement, such as squats, pushups, pull ups, bench presses, deadlifts, and bicep curls. During isotonic contraction of a skeletal muscle fiber the
A. sarcomere shorten
B. A bands shorten
C. I bands shorten
D. Both A and B
E. Both A and C
E
Which of the following is a correct statement?
A. When skeletal muscle contraction is initiated at the neuromuscular junction, ACh binds to and opens ligand gated chloride channels, resulting in the efflux of Cl- out of the skeletal muscle cell that initiates a depolarization
B. The Z line is a filamentuous protein complex that that delimits a myofibril
C. During the power stroke of skeletal muscle contraction, ADP and Pi are released as the hinge region of the myosin head undergoes a conformational change, resulting in the sliding of the actin filament in the opposite direction.
D. The A band of a sarcomere appears light in color when viewed under a microscope
E. The tropomyosin protein contains 3 subunits: one that binds to myosin, one that binds to actin and one that binds to ATP
C
A “six pack” can refer to a set of well developed, toned abdominal muscles. Muscle tone is the resting tension in a muscle generated by involuntary nervous stimulation of the muscle. Limited numbers of motor units within a muscle are usually stimulated randomly at any given time to maintain a constant tension.
Which of the following is a (are) true statement(s) with regard to motor units?
A. Motor units found in cardiac muscle are responsible for ventricular contraction
B. The total force produced by a skeletal muscle is determined by the number of motor units activated
C. The effect of exciting additional motor units is known as recruitment
D. A and B
E. B and C
E
Creatine is both synthesized in the body and derived from foods such as milk, red meat and fish. Skeletal muscle has a specific form of creatine kinase that can be used as a diagnostic tool. Which of the following is (are) true with regard to creatine and creatine kinase?
A. Creatine kinase is used to generate creatine and ATP
B. Elevated blood levels of creatine kinase can be used as a diagnostic tool that is indicative of degenerative skeletal muscle disease because normally creatine kinase is localized to the muscle cell and should not be found in the blood unless the cell is damaged.
C. The transfer of Pi from creatine phosphate to ADP to yield an ATP provides an immediate source of ATP that can be used for about a 10 second duration of energy supply.
D. A and B only
E. A, B and C
E
Which of the following statements accurately describe smooth muscle?
A. Smooth muscle has dense bodies and t tubules
B. During smooth muscle contraction, the binding of Na+ to calmodulin activates an enzyme that can phosphorylate cross bridges
C. Smooth muscle tends to fatigue rapidly
D. The thick and thin filaments in smooth muscle can be slanted
E. All of the above
D
Accumulation of lactic acid is commonly (but incorrectly) thought to cause muscle pain. Studies have shown that muscle pain is more likely to be caused by minor tearing of the skeletal muscle fibers, which results in the build-up of fluid and inflammation. When is lactic acid produced in muscle tissue?
A. Lactic acid is produced during anaerobic respiration
B. Lactic acid is produced during the lag phase of a muscle twitch, when an action potential is propagated to the post-synaptic terminal
C. Lactic acid is produced during the first 10 seconds (approximately) of activity, when ATP is supplied and used up immediately
D. Lactic acid is produced as a byproduct of creatine phosphorylation, during activity that can be sustained for hours
E. None of the above
A
During surgery to repair a fractured jaw, a patient had a very severe reaction to the inhaled general anesthetic (called sevofluorane) that he was receiving. His jaw muscles became rigid, his face was red and sweaty and his heart rate doubled. (This condition is known as malignant hyperthermia).
This patient has a mutation in the gene for the ion channels involved in releasing calcium ions from the sarcoplasmic reticulum in skeletal muscle. (These channels are named ryanodine receptor channels). When exposed to anesthetic, the mutation causes the channels to open excessively, resulting in the massive release of Ca2+ from the sarcoplasmic reticulum into the sarcoplasm.
Which of the following is (are) plausible explanations for his condition?
A. The excess Ca2+ resulted in persistent cross bridge cycling and sustained muscle contraction
B. His muscles generated a tremendous amount of heat as a byproduct of ATP production and breakdown.
C. ATP levels in his muscle became depleted, causing cross bridges to enter the rigor state.
D. The drive to maintain homeostatic pH, O2 and CO2 levels in his body triggered an increase in heart rate to support an increase in blood circulation
E. All of the above
E
