Vander's ch 6 thru ch 9, all terms
recruitment
"calling in" of receptors on additional afferent neurons
modality
another term for stimulus type (ex:heat, cold, sound or pressure etc.)
receptive field
area of body the leads to activity in a particle afferent neuron when stimulated
10. Which is TRUE about typical, resting neurons? A. The plasma membrane is most permeable to sodium ions. B. The concentration of sodium ion is greater inside the cell than outside. C. The permeability of the plasma membrane to potassium ions is much greater than its permeability to sodium ions. D. The plasma membrane is completely impermeable to sodium ions. E. The plasma membrane is completely impermeable to potassium ions.
c
10. The removal of calcium ions from the cytosol of skeletal muscle causes A. the myosin binding sites on actin to be uncovered by tropomyosin. B. tropomyosin to change conformation and thereby move troponin molecules over cross-bridge binding sites. C. troponin to change conformation and thereby expose cross-bridge binding sites. D. the myosin binding sites on actin to be covered by tropomyosin. E. None of the choices are correct.
d
11. The membrane potential of most neurons at rest is: A. equal to the equilibrium potential for potassium. B. equal to the equilibrium potential for sodium. C. slightly more negative than the equilibrium potential of potassium ion. D. more positive than the equilibrium potential for potassium. E. more positive than the equilibrium potential for sodium.
d
chemoreceptors
respond to the binding of particular chemicals to receptor membrane. this receptor provides sense of smell and taste, and detects blood pH and oxygen levels.
adequate stimulis
stimulus that a cell responds in a normal function
sensoy information
the information that the neural pathway carry from the receptors to the CNS
labeled lines
the pathways that each nerve input to the brain reports only a particular type of information
sensation
when sensory info *reaches* consciousness
acuity
precision, with which we locate and discern one stimulus from an adjacent one
photoreceptors
An electromagnetic receptor that detects the radiation know as visible light
stimulus
An energy change that affects an organism through its receptor cells
receptor potential
A slow, graded electrical potential produced by a receptor cell in response to a physical stimulus
perception
Conscious awareness of a sensation
thermoreceptors
Detect changes in temperature
mechanoreceptors
Detect touch, pressure, vibration. Usually have specialized structure
nociceptors
In animals, nerve endings that signal the sensation of pain. In humans, they are called pain receptors.
sensory receptors
Specialized cells at peripheral ends of afferent neurons that changes information into graded potential that can go into action potentials, which travel into the CNS
sensory transduction
Turning physical sensation into electrical messages
sensory system
The system of nerves/sensory receptors which carry information(stimuli) from the body's receptors to the CNS
12. The diffusion potential due to the concentration gradient for Na+ across a nerve cell membrane: A. favors its movement into the cell at the resting membrane potential. B. favors its movement out of the cell at the resting membrane potential. C. is equal and opposite to the electrical potential acting on Na+ at the resting membrane potential. D. Is in the same direction as the diffusion potential due to the concentration gradient for K+. E. favors movement of Na+ in the opposite direction as the electrical potential acting on Na+ at the resting membrane potential.
a
12. What is the definition of a "motor unit?" A. a single motor neuron plus all the muscle fibers it innervates B. a single muscle fiber plus all of the motor neurons that innervate it C. all of the motor neurons supplying a single muscle D. a pair of antagonistic muscles E. all of the muscles that affect the movement of any given joint
a
13. Which would result from an increase in the extracellular concentration of K+ above normal? A. depolarization of resting nerve cells B. hyperpolarization of resting nerve cells C. The potassium equilibrium potential of nerve cells would become more negative. D. The sodium equilibrium potential would become less positive.
a
14. Which is TRUE about the Na+, K+ ATPase pump in neurons? A. It generates a small electrical potential such that the inside is made negative with respect to the outside. B. It maintains a concentration gradient for K+ such that diffusion forces favor movement of K+ into the cell. C. It maintains an electrical gradient at the equilibrium potential of K+. D. It transports equal numbers of sodium and potassium ions with each pump cycle. E. It pumps 3 Na+ ions into the cell for every 2 K+ ions it pumps out.
a
15. Which of the following statements regarding the brain areas that direct emotion is not true? A. The hypothalamus is the site of the conscious feeling of emotion. B. The hypothalamus integrates emotional behaviors. C. The limbic system delivers information about emotion from the cerebral cortex to the hypothalamus. D. The cerebral cortex is responsible for control over emotions. E. None of the choices are true.
a
17. Myasthenia gravis is an autoimmune disease in which the immune system gradually destroys the receptors for acetylcholine at the neuromuscular junction. Which of the following drugs might initially be useful in treating the symptoms of this disease? A. a drug that inhibits acetylcholinesterase B. a drug that inhibits release of acetylcholine C. curare D. atropine (a muscarinic acetylcholine receptor antagonist) E. a nicotinic acetylcholine receptor antagonist
a
17. The equilibrium potential of K+ ions in nerve cells is about -90 mV. The membrane potential of typical nerve cells at rest is -70 mV. Therefore A. Increasing the permeability of a resting neuronal membrane to K+ will make the membrane potential more negative inside with respect to outside. B. In resting neurons, there is a net diffusion of K+ into the cell. C. changing the resting membrane potential of a neuron to -80 mV would increase K+ diffusion rate out of the cell. D. potassium is the only permanent ion at rest. E. there must be another permanent ion with an equilibrium potential more negative than -90 mV.
a
19. Schizophrenia is most strongly associated with excessive production of or sensitivity to A. dopamine. B. acetylcholine. C. norepinephrine. D. enkephalin. E. lithium carbonate.
a
23. The optimal length (Lo) of a skeletal muscle cell is: A. the length at which the muscle can generate its maximum tetanic tension. B. the shortest length the muscle can achieve while attached to bone, because the amount of overlap between thick and thin filaments is maximal then. C. generally the length attained when the joint it crosses is fully extended. D. the only length at which any tension can be generated by the muscle cell. E. the length at which thin filaments from opposite sides of a sarcomere overlap.
a
24. In the first few seconds of skeletal muscle contraction, what is the main mechanism by which ATP is replenished? A. Energy and phosphate are transferred from creatine phosphate to ADP. B. Oxidative phosphorylation rapidly generates ATP from glucose. C. Glycolysis produces ATP from glycogen. D. Oxidation of fatty acids into ATP occurs in the mitochondria. E. Myoglobin catalysis produces ATP.
a
25. Which is true about neuronal membrane electrical and concentration gradients at the peak of the action potential? A. The electrical gradient is in a direction that would tend to move K+ out of the cell. B. The concentration gradient for K+ is in a direction that would tend to move it into the cell. C. The concentration gradient for K+ greatly increases compared to at rest. D. The concentration gradient for Na+ is in a direction that would tend to move it out of the cell. E. The electrical gradient for Na+ is in a direction that would tend to move it into the cell.
a
6. The difference in electrical charge between two points: A. is called the potential difference between those points. B. is called the diffusion potential between those points. C. is called the the current, and is expressed in the units of millimoles. D. is the same for all ions.
a
7. During paradoxical sleep, A. brain neurotransmitter activity in the pathways regulating states of consciousness is similar to that in the awake state. B. brain oxygen consumption is lower than when awake. C. skeletal muscle tension is dramatically increased. D. the person is easily aroused. E. All of the choices occur.
a
8. Which best describes "rigor mortis?" A. Lack of ATP following death causes cross-bridges to remain tightly bound to actin. B. Lack of ATP following death causes calcium to remain in the cytosol, continuously stimulating cross-bridge cycling. C. Repeated, high-frequency action potentials to a skeletal muscle fiber causes sustained contraction following death. D. Following death, calcium-activated proteases degrade all proteins in skeletal muscle fibers, making muscles limp. E. Build-up of K+ in T-tubules causes constant, tetanic contractions of skeletal muscles that last for about 12 hours following death.
a
9. Which is TRUE about the resting membrane potential? A. It requires very few ions to be distributed unevenly. B. It has the same value in all cells. C. It is oriented so that the cell's interior is positive with respect to the extracellular fluid. D. Only nerve and muscle cells have a potential difference across the membrane at rest. E. It is not altered by changing concentration gradients of permeating ions.
a
sensory unit
a single afferent neuron with all its receptor endings
slowly adapting receptors
adapt slowly and continue to trigger nerve impulses as long as teh stimulus persists, slowly adapting receptors monitor stimuli associated with pain, body position, and chemical composition of the blood
1. An electroencephalogram A. is a record of action potentials in the brain. B. records the potential difference between two points on the scalp's surface. C. is a pattern of complex waves with amplitudes similar to those of action potentials. D. is both is a record of action potentials in the brain and records the potential difference between two points on the scalp's surface. E. all of these are correct: "records the potential difference between two points on the scalp's surface", "is a record of action potentials in the brain", and "records the potential difference between two points on the scalp's surface" are correct
b
1. Which best describes a "myofibril?" A. It is a single skeletal-muscle cell. B. It is a cylindrical cellular organelle composed of myofilaments. C. It is a hollow membranous structure that stores calcium. D. It is composed of a single type of protein and forms cross-bridges. E. It is a fibrous junction between a muscle cell and a tendon.
b
11. This part of the brain is thought to control the various states of consciousness. A. cerebral cortex B. reticular activating system C. thalamus D. cerebellum E. hippocampus
b
15. Which of these would occur if the concentration of ATP were depleted in a typical nerve cell? A. Resting membrane potential would become more negative. B. Resting membrane potential would become less negative. C. The concentration gradient for Na+ would remain the same. D. The resting membrane potential would eventually become positive inside with respect to outside. E. There would be no change in the resting membrane potential.
b
16. Damage to the septum of the limbic system causes a tame animal to become vicious, whereas destruction of the amygdala will make the same animal docile again. Which of the following statements may explain this result or correctly follow from it? A. The septum is required for the expression of rage. B. In a normal animal, the septum may inhibit the amygdala. C. Stimulation of the septum in a normal animal would be likely to provoke rage. D. Both "the septum is required for the expression of rage" and "in a normal animal, the septum may inhibit the amygdala" are correct. E. All of the choices are correct.
b
2. It is believed that the rhythmic patterns of the EEG most likely originate from this structure in the brain. A. hypothalamus B. thalamus C. basal ganglia D. cerebellum E. hippocampus
b
2. What protein is the principle component of skeletal muscle thick filaments? A. actin B. myosin C. troponin D. calmodulin E. tropomyosin
b
20. Drugs that are used to treat depression increase the levels of this neurotransmitter in the brain. A. glutamate B. serotonin C. GABA D. acetylcholine E. dopamine
b
20. An action potential in a neuronal membrane differs from a graded potential in that: A. an action potential requires the opening of Ca2+ channels, whereas a graded potential does not. B. an action potential is propagated without decrement, whereas a graded potential decrements with distance. C. an action potential has a threshold, whereas a graded potential is an all-or-none phenomenon. D. movement of Na+ and K+ across cell membranes mediate action potentials, while graded potentials do not involve movement of Na+ and K+. E. action potentials vary in size with the size of a stimulus, while graded potentials do not.
b
21. What is the best description of a tetanic contraction in a skeletal muscle cell? A. A single action potential in the motor neuron causes a sustained contraction. B. Multiple action potentials in the motor neuron cause a sustained contraction. C. The action potential in the muscle cell is prolonged to last as long as the contraction. D. Repeated action potentials from the motor neuron summate into a sustained depolarization of the motor end plate, causing a sustained contraction. E. A very large amplitude action potential in the motor neuron causes a very strong contraction in the skeletal muscle cell.
b
22. Which must happen in order for an action potential to begin? A. The membrane potential must be at the Na+ equilibrium potential. B. Na+ influx must exceed K+ efflux. C. The membrane must be out of the relative refractory period. D. Na+ channels must all be inactivated. E. Multiple inhibitory postsynaptic potentials (IPSPs) must summate.
b
23. Which describes the response of the voltage-gated channels when an axon is stimulated to threshold? A. K+ channels open before the Na+ channels. B. Na+ channels are activated and then inactivated. C. K+ channels open at the same time as the Na+ channels. D. K+ channels are opened when Na+ binds to the channel. E. K+ influx causes Na+ channels to inactivate.
b
24. During the rising (depolarizing) phase of a neuronal action potential, A. PK+ becomes much greater than PNa+. B. PNa+ becomes much greater than PK+. C. PK+ is the same as PNa+. D. Na+ efflux (flow out of the cell) occurs. E. K+ flows rapidly into the cell.
b
4. If you were to record your own EEG activity while concentrating very hard on this exam, the most prominent EEG pattern would be A. alpha rhythm. B. beta rhythm. C. delta rhythm. D. theta rhythm.
b
5. Which of the following is not true of glial cells? A. They form the myelin for axons. B. Neurons outnumber glial cells 10 to 1 in the nervous system. C. They deliver fuel molecules to neurons and remove the waste products of metabolism. D. They are important for the growth and development of the nervous system. E. They regulate the composition of the extracellular fluid in the CNS.
b
6. Binding of ________ to myosin permits cross-bridge _____________ between actin and myosin in skeletal muscle cells. A. ATP; attachment B. ATP; detachment C. calcium; attachment D. calcium; detachment E. actin; detachment
b
6. Which of the following is not descriptive of REM sleep? A. It is the period when dreaming occurs. B. It normally occurs only once per night, usually just before waking up. C. Postural muscles are virtually paralyzed during REM sleep. D. EEG waves that resemble the awake state can be recorded during REM sleep. E. Eyes move rapidly back and forth beneath closed lids.
b
7. Which occurs FIRST as a result of ATP binding to myosin? A. cross-bridge heads are cocked into an "energized" state B. actin dissociates from from myosin C. Ca2+ is released from the sarcoplasmic reticulum D. actin binds to myosin E. cross-bridges rotate, sliding past the thin filament
b
11. Which of the following statements is TRUE regarding skeletal-muscle contraction? A. Only one cross-bridge cycle can occur when the [Ca2+] is elevated in the cytosol; in order to undergo a second cycle, [Ca2+] must be sequestered in the sarcoplasmic reticulum and released again. B. ATP hydrolysis products must be removed from myosin before it can bind to actin. C. Binding of myosin to actin takes place when [Ca2+] increases in the cytosol. D. A single twitch in skeletal muscle lasts the same length of time as the action potential that causes it. E. The powerstroke of the cross-bridge cycle occurs simultaneously with ATP being hydrolyzed into ADP and Pi.
c
13. What is the function of the transverse tubules in a skeletal-muscle fiber? A. They store the calcium ions that are the main source of activation for the cross-bridge cycle. B. They form the Z lines that mark the end of each sarcomere. C. They allow action potentials to propagate deep into the center of skeletal muscle cells. D. They manufacture and store ATP. E. They run in parallel with the myofibrils, and have abundant Ca2+-ATPase proteins for pumping Ca2+ back into the sarcoplasmic reticulum.
c
15. Which of the following statements regarding the motor end plate of a skeletal-muscle fiber is TRUE? A. Muscarinic receptors in the end plate are activated by binding to acetylcholine. B. Temporal summation of multiple end plate potentials is required in order to trigger an action potential in the muscle-fiber membrane. C. Acetylcholinesterase in the end plate membrane catalyzes the breakdown of acetylcholine. D. Sympathetic nerve fibers terminate on skeletal muscle fibers at the motor end plate. E. The motor end-plate under the axon terminal contains a large number of voltage-gated Na+ channels.
c
18. Which of these occurs during an isometric contraction of a skeletal muscle? A. The I bands shorten and the A bands stay the same length. B. The thick and thin filaments slide past each other. C. Sarcomere length does not change. D. The A bands shorten and the I bands stay the same length. E. Cross-bridges lock onto actin, similar to what occurs in rigor mortis.
c
19. During an isometric twitch in a skeletal muscle: A. tension generated by the muscle always exceeds the load on the muscle. B. tetanus occurs. C. sarcomeres do not significantly shorten. D. the whole muscle shortens. E. the load on the muscle is always greater than the tension generated.
c
21. A threshold stimulus applied to an excitable membrane is one that is just sufficient to: A. trigger an excitatory postsynaptic potential. B. cause a change in membrane potential. C. trigger an action potential. D. be conducted to the axon hillock. E. depolarize a dendrite.
c
25. When a muscle has been repeatedly contracting at a moderate intensity for an extended period of time (more than a few minutes), what is the primary source of ATP? A. transfer of energy and phosphate from creatine phosphate to ADP B. glycolysis C. oxidative phosphorylation D. breakdown of myosin E. uptake of ATP from the blood plasma
c
3. During concentric isotonic contraction of a skeletal-muscle fiber, which of these occurs? A. sarcomeres lengthen B. A bands shorten C. I bands shorten D. A bands lengthen E. thin filaments shorten
c
3. The alpha rhythm is the most prominent EEG pattern when an adult is A. in REM sleep. B. in non-REM sleep. C. awake and relaxed with eyes open. D. awake and thinking hard about something.
c
3. Which of the following is not true about axon transport? A. It refers to the passage of materials from the cell body of a neuron to the axon terminals. B. It refers to the passage of materials from axon terminals to the cell body of a neuron. C. It refers to the transport of materials from the inside to the outside across the axonal membrane. D. It is especially important for maintaining the integrity of neurons with long axons.
c
4. Which of the following statements regarding contraction of a skeletal-muscle fiber is TRUE? A. Thick filaments shorten when muscle cells contract. B. Some contractions occur without cross-bridge activation. C. Contracting muscle fibers do not always shorten. D. Contraction does not always require the occurrence of an action potential. E. Contraction only occurs following summation of action potentials from many motor neurons.
c
5. In skeletal muscle cells, calcium initiates contraction by binding to: A. tropomyosin. B. actin. C. troponin. D. myosin. E. the thick filament.
c
7. According to the equation expressed as Ohm's law, which of these would cause the greatest increase in current? A. doubling both voltage and resistance B. reducing both voltage and resistance by half C. doubling voltage and reducing resistance by half D. reducing voltage by half and doubling resistance E. quadrupling both voltage and resistance
c
8. Which of the following most accurately describes the state of consciousness known as REM sleep? A. EEG tracings show large amplitude, low frequency waves; subject has very low muscle tone; if awakened will usually report dreaming B. EEG tracings show low amplitude, high frequency activity; subject has normal muscle tone; if awakened will usually report dreaming C. EEG tracings show low amplitude, high frequency activity; subject has very low muscle tone; if awakened will usually report dreaming D. EEG tracings show low amplitude, high frequency activity; subject has normal muscle tone; if awakened will not usually report dreaming E. EEG tracings show large amplitude, low frequency waves; subject has normal muscle tone; if awakened will usually report dreaming
c
9. Which of the descriptions is not descriptive of REM (Rapid Eye Movement) sleep? A. visible movements of the eyes resembling those of one tracking the movements of objects in space, watching TV, etc B. difficulty arousing the sleeper C. oxygen consumption decreases by comparison to NREM sleep and in an alert wakeful state D. it represents 20-25% of a person's "sleep time" E. skeletal muscle activity is markedly reduced, except for the extraocular and respiratory muscles
c
coding
conservation of stimulus energy into a signal that conveys the relevant sensory info to the CNS
13. Regarding its role as a neurotransmitter in the CNS, norepinephrine A. is secreted by brain stem neurons in response to sensory stimulation. B. amplifies weak sensory signals and dampens strong ones so that more information can reach conscious levels. C. is important for maintaining directed attention. D. both "is secreted by brain stem neurons in response to sensory stimulation" and "is important for maintaining directed attention" are correct. E. All of the choices are correct.
d
14. A laboratory rat has an electrode implanted in its brain. By pressing a metal bar in its cage, the animal can activate the electrode. Which of the following is most likely to be true? A. If the animal presses the bar repeatedly, then the electrode is probably in an area associated with appetitive motivation. B. If the animal presses the bar once, then never touches it again, then the electrode is probably in an area associated with aversive motivation. C. Such an experiment has no relevance to emotional states in humans or human behavior. D. Both if the animal presses the bar repeatedly, then the electrode is probably in an area associated with appetitive motivation and if the animal presses the bar once, then never touches it again, then the electrode is probably in an area associated with aversive motivation are correct. E. All of the choices are correct.
d
14. An action potential in the motor end plate rapidly spreads to the interior regions of a muscle cell by means of the: A. Z lines. B. sarcoplasmic reticulum. C. H zone. D. transverse tubules. E. pores in the plasma membrane.
d
16. How does the chemical curare affect skeletal muscle function? A. It activates an autoimmune disease that destroys myelin. B. It blocks the action of acetylcholinesterase at the neuromuscular junction. C. It is a muscarinic acetylcholine receptor antagonist that blocks synaptic transmission at the neuromuscular junction. D. It is a nicotinic acetylcholine antagonist that blocks synaptic transmission at the neuromuscular junction. E. It locks ligand-gated channels in the open state, leading to spastic contractions of muscle.
d
18. Regarding schizophrenia, A. People with schizophrenia frequently have disorders of sensory awareness. B. Treatment of schizophrenia may result in symptoms of Parkinson's disease. C. Lithium carbonate is the most common drug prescribed for schizophrenia. D. Both "people with schizophrenia frequently have disorders of sensory awareness" and "treatment of schizophrenia may result in symptoms of Parkinson's disease" are correct. E. Both "treatment of schizophrenia may result in symptoms of Parkinson's disease" and "lithium carbonate is the most common drug prescribed for schizophrenia" are correct.
d
18. Which of the following statements concerning the permeability of a typical neuron membrane at rest is true? A. The permeability to Na+ is much greater than the permeability to K+. B. All of the K+ channels in the membrane are open. C. The voltage-gated Na+ channels are in the inactivated state. D. Most of the voltage-gated Na+ channels are in the closed state. E. There is equal permeability to Na+ and K+.
d
2. Which is not true of myelin? A. It is a fatty membranous sheath. B. It is formed by glial cells. C. It influences the velocity of conduction of an electrical signal down an axon. D. It covers all parts of the neuron, including the axon, cell body, and dendrites.
d
20. Which of the following statements regarding skeletal-muscle contraction is true? A. During a lengthening contraction, the tension exerted by the muscle exceeds the load on the muscle. B. In every isotonic muscle contraction, the length of the muscle remains constant. C. During every muscle contraction, muscle fibers change length. D. During every muscle contraction, tension is developed in the muscle. E. Cross-bridges cycle faster during isometric contractions than during isotonic contractions.
d
24. Which of the following best explains how the phenomenon of "tolerance" develops with use of psychoactive drugs over time? A. Psychoactive drugs can alter blood flow to the brain. B. Psychoactive drugs often produce euphoria. C. Psychoactive drugs can cross the blood-brain barrier. D. Psychoactive drugs can inhibit production of endogenous neurotransmitters. E. Psychoactive drugs can up-regulate receptors for endogenous neurotransmitters.
d
25. Symptoms of withdrawal when drug use is stopped A. may result from lower-than-normal secretion of neurotransmitter. B. are psychological, not physical. C. may be alleviated by taking a drug that interacts with the same receptor as the original drug. D. both "may result from lower-than-normal secretion of neurotransmitter" and "may be alleviated by taking a drug that interacts with the same receptor as the original drug" are correct. E. All of the choices are correct.
d
8. Compartments A and B are separated by a membrane that is permeable to K+ but not to Na+ or Cl-. At time zero, a solution of KCl is poured into compartment A and an equally concentrated solution of NaCl is poured into compartment B. Which would be true once equilibrium is reached? A. The concentration of Na+ in A will be higher than it was at time zero. B. Diffusion of K+ from A to B will be greater than the diffusion of K+ from B to A. C. There will be a potential difference across the membrane, with side B negative relative to side A. D. The electrical and diffusion potentials for K+ will be equal in magnitude and opposite in direction. E. The concentration of Cl- will be higher in B than it was at time zero.
d
9. Rigor mortis is caused by: A. buildup of lactic acid. B. lack of Ca2+. C. depletion of glycogen. D. lack of ATP. E. deficient acetylcholine receptors.
d
adaptation
decrease in receptor sensitivity, results in decrease in action potential frequency in afferent neuron
1. Which of the following is/are functions of the human nervous system? A. receiving, storing, and processing information on the internal and external environments B. bringing about changes in physiology and/or behavior to ensure optimal functions of homeostatic mechanisms C. secretion of hormones D. coordination of movement E. All of the choices are correct.
e
10. In sleep apnea A. a person with the disorder experiences symptoms of sleep deprivation. B. periodic bouts of respiratory failure are experienced throughout the night. C. slow-wave and REM sleep predominate in sleep cycling. D. seriously low blood O2 levels result. E. All of the choices are correct.
e
12. Habituation to a stimulus A. is due to receptor fatigue. B. is a result of decreased neurotransmitter release secondary to decreased calcium influx at synaptic terminals. C. can be overcome by a stronger stimulus of the same type. D. both "is due to receptor fatigue" and "can be overcome by a stronger stimulus of the same type" are correct. E. both "is a result of decreased neurotransmitter release secondary to decreased calcium influx at synaptic terminals" and "can be overcome by a stronger stimulus of the same type" are correct.
e
16. Which is FALSE about the equilibrium potential of a given ion across a membrane? A. It is a function of the concentration of that ion on both sides of the membrane. B. It is the potential at which there is no net movement of that ion across the membrane. C. It is the potential difference across the membrane at which an electric force favoring movement of the ion in one direction is equal in magnitude and opposite in direction to the diffusion force provided by the concentration difference of the ion across the membrane. D. A permeable ion will move in the direction that will tend to bring the membrane potential toward that ion's equilibrium potential. E. An anion that is in higher concentration inside the cell than outside the cell will have a negative eqilibrium potential.
e
17. Regarding schizophrenia, A. It is a family of mental disorders that involves disturbances of thinking, perceiving and control of motor activity. B. Its symptoms can include paranoid delusions and hallucinations. C. It probably has a hereditary component. D. Both "it is a family of mental disorders that involves disturbances of thinking, perceiving and control of motor activity" and "its symptoms can include paranoid delusions and hallucinations" are correct. E. All of the choices are correct.
e
19. Which is NOT an example of a graded potential? A. a receptor potential in a sensory receptor cell B. a depolarizing excitatory postsynaptic potential (EPSP) C. a hyperpolarizing inhibitory postsynaptic potential (IPSP) D. a depolarizing pacemaker potential E. a depolarizing action potential
e
21. Bipolar disorders A. involve both mania and depression. B. are most effectively treated with drugs that increase availability of dopamine. C. are an exaggeration of normal changes in mood. D. both "involve both mania and depression" and "are most effectively treated with drugs that increase availability of dopamine" are correct. E. both "involve both mania and depression" and "are an exaggeration of normal changes in mood" are correct.
e
22. How is the length of a skeletal muscle cell related to the force it can generate? A. The tension in a skeletal muscle cell is greatest when contractions occur at either very short or very long lengths. B. Skeletal muscle cells generate the same amount of force, regardless of their length. C. The shorter a skeletal muscle cell is when it begins to contract, the stronger the force generation will be. D. The longer a skeletal muscle cell is when it begins to contract, the stronger the force generation will be. E. Skeletal muscle cells generate the most force when the contraction occurs at an intermediate length.
e
22. Regarding psychoactive drugs, A. they can be taken to relieve altered states of consciousness. B. they can be taken to experience altered states of consciousness. C. they may stimulate neuronal activity in the "reward" areas of the brain. D. both "they can be taken to experience altered states of consciousness" and "they may stimulate neuronal activity in the 'reward' areas of the brain" are correct. E. All of the choices are correct.
e
23. Regarding psychoactive drugs, A. both the phenomenon of "tolerance" to and the symptoms of "withdrawal" from a psychoactive drug can be explained by the positive feedback effect of the drug on the production of the endogenous neurotransmitter/neuromodulator for which the drug is an agonist. B. Only drugs that bind to endorphin/enkephalin receptors are described as "psychoactive." C. use of psychoactive drugs may result in physical dependence upon them. D. both "the phenomenon of 'tolerance' to and the symptoms of 'withdrawal' from a psychoactive drug can be explained by the positive feedback effect of the drug on the production of the endogenous neurotransmitter/neuromodulator for which the drug is an agonist" and "only drugs that bind to endorphin/enkephalin receptors are described as 'psychoactive'" are correct. E. both "the phenomenon of 'tolerance' to and the symptoms of 'withdrawal' from a psychoactive drug can be explained by the positive feedback effect of the drug on the production of the endogenous neurotransmitter/neuromodulator for which the drug is an agonist" and "use of psychoactive drugs may result in physical dependence upon them" are correct.
e
4. Which is FALSE about neurons? A. A given neuron can be either a presynaptic neuron or a postsynaptic neuron. B. An individual neuron can receive information from multiple other neurons. C. An individual neuron can transmit information to multiple other neurons. D. A neuron can simultaneously release more than one type of neurotransmitter. E. A neuron receives information on its axons and delivers it to other neurons through its dendrites.
e
5. Which of the following statements about sleep is correct? A. Sleep typically occurs in stages in which a subject goes through progressively deeper stages of sleep and then awakens. B. Sleep typically occurs in cycles in which a subject will cycle through various stages of slow-wave sleep punctuated by paradoxical sleep several times during one bout of sleep. C. During REM sleep, blood pressure and breathing rate become elevated. D. Both "sleep typically occurs in stages in which a subject goes through progressively deeper stages of sleep and then awakens" and "during REM sleep, blood pressure and breathing rate become elevated" are correct. E. Both "sleep typically occurs in cycles in which a subject will cycle through various stages of slow-wave sleep punctuated by paradoxical sleep several times during one bout of sleep" and "during REM sleep, blood pressure and breathing rate become elevated" are correct.
e
rapidly adapting receptors
generate receptor potential and action potential at the onset of a stimulus but very quickly cease responding
lateral inhibition
mechanism enabling the localization of a stimulus site for some sensory systems
