NPB101 Final Practice questions

During muscle contraction, what becomes smaller or remains the same length?

Shorter: Sarcomere, H zone, and I band Same length: A band, actin, and myosin fibers

List the three types of muscle and examples. What are the structural and functional differences?

1. Skeletal muscle: Attached skeleton, Voluntary, Long, cylindrical, and striated, Multiple nuclei, peripheral 2. Cardiac muscle: Walls of the heart, involuntary, Cylindrical, Branched and striated, one-two nuclei, central 3. Smooth muscle: Walls of the stomach and intestine, involuntary, spindle-shaped, unstriated, single nucleus

If someone has a stroke volume of 70 ml and a heart rate of 90 beats/min, the cardiac output equals A) 6.3 L/min B) 0.77 L/min C) 70 ml/min D) 1.28 ml/min E) 0.63L/min

A) 6.3 L/min

Which of the following would NOT result in an increase in filtration of fluids from capillaries to the surrounding tissue (tissue edema)? A) An increase in the concentration of plasma protein B) An increase in the pore size of the capillaries in the body C) An increase in venous pressure D) An increase in the arterial pressure A decrease in the hydrostatic pressure from the interstitial fluid.

A) An increase in the concentration of plasma protein

There is/are ________ pulmonary vein(s) emptying into the right atrium of the heart. A) No B) One or Two C) Three D) Four E) More than four

A) No

The following steps refer to various stages in transmission at a synapse. 1. Neurotransmitter binds with receptors associated with the postsynaptic membrane. 2. Voltage gated Ca2+ channels open in the presynaptic terminal 3. An action potential depolarizes the membrane of the axon terminal. 4. Ligand-gated ion channels open. 5. Neurotransmitters are released into the synaptic cleft. Which sequence of events is correct? A. 3 → 2 → 5 → 1 → 4 B. 3 → 2 → 5 → 4 → 1 C. 4 → 3 → 1 → 2 → 5 D. 5 → 1 → 2 → 4 → 3 E. 1 → 2 → 3 → 4 → 5

A. 3 → 2 → 5 → 1 → 4

Which of the following is a primary tissue type specialized for structural support? A. Connective B. Oxidative. C. Microtubulea D. None of the above

A. Connective

Which of the following is NOT a generalized function of all cell types? A. Generate and transmit electrical impulses B. Metabolizing fuel C. Synthesizing proteins D. Eliminating waste E. Movement

A. Generate and transmit electrical impuleses

The equilibrium potential for anion Z- is +80 mV. Assume a mammalian neuron at rest. A. Opening a channel permeable to Z- would depolarize a cell. B. There is a higher concentration of Z- outside the cell than inside. C. Z- has the same concentration gradient as chloride (Cl-) D. A and B are correct E. A, B and C are correct

A. Opening a channel permeable to Z- would depolarize a cell.

If all other conditions remain the same and the concentration of a non-penetrating/ impermeable solute increases inside a cell, A. Water will tend to enter the cell because the interior has an increased osmolarity B. Water will tend to leave the cell because the interior has an increased osmolarity C. Water will tend to enter the cell because the interior has a decreased osmolarity D. Water will tend to leave the cell because the interior has a decreased osmolarity E. The non-penetrating solute will diffuse across the membrane until its concentration is equal on both sides of the membrane

A. Water will tend to enter the cell because the interior has an increased osmolarity

In a homeostatic system, the efferent signal carries info directly: A. from the integrator to the effector b. from the sensor to the integrator C. from the sensor to the integrator D. from the effector to the response E. from the effector to the integrator

A. from the integrator to the effector

Myasthenia gravis is an autoimmune disease involving the neuromuscular junction, in which antibodies impair the communication between nerve and muscle cells. Which treatment/s can be applied to remedy the impaired communication? A. increase the amount of acetylcholine by reducing the rate of acetylcholine degradation. B. decrease the amount of acetylcholine by increasing the rate of acetylcholine degradation. C. Acetylcholine inhibitor D. Acetylcholine receptor inhibitor. E. Both C and D

A. increase the amount of acetylcholine by reducing the rate of acetylcholine degradation.

Based on your knowledge of ionotropic and metabotropic receptors, which of the following pairings is correct? A. ionotropic; direct opening of an ion channel B. ionotropic; more time required to open an ion channel than for metabotropic receptors. C. ionotropic; G-protein activation leads to activation of a second messenger D. metabotropic; direct opening of an ion channel. E. metabotropic; second messengers conduct current into the cell.

A. ionotropic; direct opening of an ion channel

What would happen to the membrane potential of a cell that is permeable only to K+ if the extracellular concentration of K+ suddenly increased by 50%? A. it would depolarize B. there would be no change C. it would hyperpolarize and then depolarize D. it would hyperpolarize E. There is not enough information to answer this question.

A. it would depolarize

In the homeostatic system that regulates body temperature in humans, the sensors are: A. temperature monitoring nerve cells B. sweat glands C. hypothalamic neurons D. skeletal muscles E. brown adipocytes

A. temperature monitoring nerve cells

If a cell is placed in a hypotonic solution, it A. will swell B. will shrink C. will stay the same size D. will shrink first, but then will return to its original size E. there is not enough information to answer this question

A. will swell

Measurements in a nephron reveal a glomerular hydrostatic pressure of 69 mm Hg, and a fluid pressure in the Bowman's capsule of 15 mm Hg. Assuming that the plasma osmotic pressure is 30 mm Hg, and that essentially no plasma proteins are filtered by the glomerulus, what is the net glomerular filtration pressure in this case? A) -6 mm Hg B) 24 mm Hg C) 54 mm Hg D) 84 mm Hg E) 114 mm Hg

B) 24 mm Hg

Aldosterone A) is secreted in response to elevated levels of potassium in the blood. B) promotes sodium retention in the kidneys. C) helps decrease blood volume. D) increases the concentration of sodium in urine. E) functions in pH regulation.

B) promotes sodium retention in the kidneys.

Osmoreceptors depolarize after they ________ in response to ________ plasma osmolarity. A) shrink, decreased B) shrink, increased C) swell, decreased D) swell, increased

B) shrink, increased

In order for blood to enter the heart, it is absolutely necessary that A) the atria be in diastole. B) the pressure in the atria be lower than in the veins. C) the AV valves be open. D) A and B E) A, B, and C

B) the pressure in the atria be lower than in the veins.

Signals that a cell sends to itself represent a form of: A. Endocrine communication B. Autocrine communication C. Paracrine communication D. Electrical communication E. Pheromonal communication

B. Autocrine communication

Which of the following is true about the relative refractory period? A. It is due to the inactivation of the voltage gated sodium channels. B. It is due to the voltage gated potassium channels being open. C. It is a period where it is impossible to fire an action potential. D. A and b are correct. E. A, and c are correct.

B. It is due to the voltage gated potassium channels being open.

Coding sound for pitch is a function of the A. tectorial membrane. B. basilar membrane. C. vestibular membrane. D. endolymph.E. ossicles.

B. basilar membrane.

Sodium Potassium ATPase A. transports 3 Na into the cell B. is an example of primary active transport C. transports 2 K out of the cell D. A and B are correct E. A, B and C are correct

B. is an example of primary active transport

In order to signal a stronger stimulus, action potentials become A. higher in amplitude. B. more frequent. C. longer lasting. D. A and B E. A and C

B. more frequent.

If neuron X is excitatory and fires multiple action potentials to bring neuron W to threshold... A. spatial summation is taking place. B. temporal summation is taking place. C. the cell will only respond to the first action potential. D. All of the above are true. E. None of the above is true.

B. temporal summation is taking place.

The depolarization indicated at "2" is caused by opening of the ____________, allowing __________. A. voltage gated Na+ channel; Na+ ions to leave the cell. B. voltage gated Na+ channel; Na+ ions to enter the cell C. voltage gated K+ channel; K+ ions to leave the cell D. voltage gated K+ channel; K+ ions to enter the cell. E. voltage gated Na+ and Ca2+ channels; both ions to enter the cell.

B. voltage gated Na+ channel; Na+ ions to enter the cell

Explain why muscles are stiff during rigor mortis.

Because of lack of fresh ATP, the cross bridge cannot detach from the actin filaments, and therefore, the muscle becomes rigid.

Which of the following events result in the second heart sound? A) The AV valves open. B) The AV valves close. C) The semilunar valves close. D) The semilunar valves open. E) The atria contract.

C) The semilunar valves close.

You accidently swallow a high dose of the drug Ivabridine, which specifically blocks the "funny" channels in your sinoatrial node cells. Which of the following is true? A) This will result in an increase in heart rate. B) There will be an effect similar to what is seen when the sympathetic system is stimulated. C) There will be an effect similar to what is seen when the parasympathetic system is stimulated. D) This will result in an increase in the width of the myocardial action potential. E) A and B are correct.

C) There will be an effect similar to what is seen when the parasympathetic system is stimulated.

When a body is dehydrated, water in the urinary bladder A) can be returned to the circulation directly. B) can be returned to the circulation after moving back into the kidneys. C) will still be expelled from the body in the urine.

C) will still be expelled from the body in the urine.

Which sequence of events is correct? A. 1 → 2 → 3 → 4 → 5 B. 3 → 2 → 5 → 4 → 1 C. 3 → 2 → 5 → 1 → 4 D. 4 → 3 → 1 → 2 → 5 E. 5 → 1 → 2 → 4 → 3

C. 3 → 2 → 5 → 1 → 4

Select the correct statement regarding acuity. A. The larger receptive fields and the greater density of receptors cause a higher acuity in the region. B. The smaller receptive fields and the greater density of receptors cause a lower acuity in the region. C. Acuity is determined by the density of receptors, the size of receptive fields, and lateral inhibition. D. The higher number of sensory receptors in a region, the less accurate the sensory perception of the area. E. Lateral inhibition results in a broadening of receptive fields.

C. Acuity is determined by the density of receptors, the size of receptive fields, and lateral inhibition.

Why do we have blind spots in our visual fields? A. Because we have macular degeneration. B. Because there are no rods in the fovea. C. Because there are no photoreceptors in the optic disc. D. Because fovea has high visual acuity. E. Because rhodopsin is inactive in the darkness.

C. Because there are no photoreceptors in the optic disc.

In a given negative feedback control system, the sensor becomes non-functional (it is 'broken'). As a result: A. The afferent signal is elevated/increased B. The efferent signal is elevated/increased C. Homeostasis of this variable cannot be maintained D. Both A and B are correct E. A, B and C are correct.

C. Homeostasis of this variable cannot be maintained

EVERYONE GOT CREDIT Which of the following statements about saltatory conduction of action potentials is/are FALSE? A. The first action potential is triggered in the axon hillock. B. Conduction of the electrical signal between neighboring nodes of Ranvier is similar to conduction of electrical signals in dendrites. C. The action potential is regenerated at the nodes of Ranvier because those are the sites of lowest concentration voltage gated Na+ and K+ channels. D. It takes place in myelinated axons. E. B and C are both FALSE. (so this would be the right answer if that is the case)

C. The action potential is regenerated at the nodes of Ranvier because those are the sites of lowest concentration voltage gated Na+ and K+ channels.

A person suffers from a strange disease whereby his neurons have no voltage sensitive potassium channels. As a consequence... A. the rate at which an action potential reaches its peak would be slower than normal. B. there would be no absolute refractory period. C. following generation of an action potential, recovery to normal resting membrane potential would be slower than normal. D. The undershoot of the action potential will be deeper (more negative) than normal. E. A and C are correct.

C. following generation of an action potential, recovery to normal resting membrane potential would be slower than normal.

in a homeostatic system, the afferent signal carries information directly: A. from the integrator to the effector B. from the effector to the integrator C. from the sensor to the integrator D. from the effector to the response E. from the effector to the integrator

C. from the sensor to the integrator

You went to the classical music concert at Mondavi Center. The music started with lower pitch sounds and ended on a higher pitch sound. High- and low-frequency sounds are discriminated chiefly by: A. high frequencies producing stronger vibrations. B. low frequencies producing larger action potentials. C. low frequencies deflecting the basilar membrane at a greater distance from the oval window. The hair cells are depolarized. D. low frequencies deflecting the basilar membrane at a greater distance from the oval window. The hair cells are hyperpolarized. E. high frequencies deflecting the basilar membrane at a greater distance from the oval window. The hair cells are depolarized.

C. low frequencies deflecting the basilar membrane at a greater distance from the oval window. The hair cells are depolarized

The larger the receptive field, A. the larger the stimulus needed to stimulate a sensory receptor .B. the more sensory receptors it includes. C. the harder it is to discriminate the exact point of stimulation. D. the larger the area of the somatosensory cortex in the brain that deals with the area.E. all of the above

C. the harder it is to discriminate the exact point of stimulation.

Describe the differences between slow-oxidative vs. fast-glycolytic muscle fibers.

Check table 8-1 Characteristic of Skeletal muscle fibers in the lecture slide PDF file.

If the ATP-generating mechanisms in a cell are poisoned and the cell depletes its ATP reserves A. primary active transport of molecules would cease immediately b. secondary active transport of molecules would cease immediately C. eventually there will be no potential difference across the membrane D. A & C E. A, B, and C are correct

D . A & C

During isovolumetric contraction of the ventricles... A) the atrioventricular valves are open while the pulmonary and aortic valves are closed B) the atrioventricular valves are closed while the pulmonary and aortic valves are open C) all cardiac valves are open D) all cardiac valves are closed E) ventricular pressure is constant

D) all cardiac valves are closed

Which of the following would result in an immediate increase in the ventricular end-diastolic volume? A) hemorrhage B) decrease in sympathetic activity to the veins. C) increase in arterial pressure. D) increased skeletal muscle pump E) none of the above

D) increased skeletal muscle pump

Contents in the peritubular capillaries are actively transported into proximal and distal convoluted tubules in a process known as: A) excretion B) filtration C) reabsorption D) secretion E) encretion

D) secretion

Which of the following statements about the opening of the voltage gated K+ channels during an action potential is/are correct? A. The opening of the voltage gated K+ channels is triggered when the cell membrane crosses threshold from a more negative to a less negative membrane value. B. Voltage gated K+ channels require that the action potential reaches its peak value to be able to open. C. The opening of the voltage gated K+ channels is slower than that of the voltage gated Na+ channels. D. A and C are correct E. A, B and C are correct

D. A and C are correct

You are trying to find the most effective inhibitory input that you can give to a cell. We measure effectiveness by their ability to prevent cells from firing an action potential. Which of these conformations would give you the most effective inhibitory input? A. A small inhibitory input located far away in the dendrites. B. A large inhibitory input located far away in the dendrites. C. A small inhibitory input located in the proximal dendrite / close to soma. D. A large inhibitory input located in the proximal dendrite / close to soma. E. A large inhibitory input located in the axon terminal.

D. A large inhibitory input located in the proximal dendrite / close to soma.

Amplification during a second messenger cascade is beneficial because amplification A. Takes small molecules and makes polymers out of them B. Results in the production of more of the first messenger C. Allows a cell to respond to a greater variety of hormones D. Allows small amounts of hormones to produce large responses in target cells E. None of the choices are correct

D. Allows small amounts of hormones to produce large responses in target cells

Why is Phineas Gage famous? A. Because he survived an injury in which the front part of the left side of his brain was damaged. This brain region is essential for creating new memories. B. Because he performed prefrontal lobotomies as a treatment for personality disorders, which was not a humane method of treatment. C. Because a serious accident happened for the first time in American railroad history. D. Because his case revealed, for the first time, that damage in the frontal lobe could lead to personality changes. E. Because he was a famous neuroscientist.

D. Because his case revealed, for the first time, that damage in the frontal lobe could lead to personality changes.

Closing the leak K+ channels after an action potential is fired would cause: A. The "5" to be a more depolarized value, but would not affect the "3" value. B. The "5" to be a more depolarized value and the "3" to be a more hyperpolarized/negative value. C. Both "5" and "3" would be more hyperpolarized / negative. D. Both "5" and "3" would be more depolarized / positive. E. None of the parameters of the action potential would be affected.

D. Both "5" and "3" would be more depolarized / positive.

In a given negative feedback control system, the EFFECTOR becomes non-responsive to incoming information (it is broken) as a result: A. the afferent signal is elevated/increased B. The efferent signal is elevated/increased C. Homeostasis is maintained D. Both A and B are correct

D. Both A and B are correct

Which of the following statements is correct? A. The central nervous system includes brain, spinal cord, cranium, and vertebral column. B. Meninges are the bones that wrap, protect, and nourish the central nervous system. C. The autonomic nervous system controls motor neurons. D. Sensory neurons are located in the peripheral nervous system. E. The somatic nervous system controls the sympathetic and parasympathetic nervous systems.

D. Sensory neurons are located in the peripheral nervous system.

The return to rest that happens after "5" is caused by A. The closing of voltage gated Na+ channels, thus not allowing Na+ ions to leave the cell. B. The opening of voltage gated K+ channels; allowing K+ ions to enter the cell. C. The inactivation of the voltage gated Na+ channels. D. The flow of ions through the leak channels. E. B and D are correct.

D. The flow of ions through the leak channels.

Whether a synapse is excitatory or inhibitory is determined by the A. The number of action potentials arriving at the presynaptic terminal. B. The amount of the calcium ions flowing into the presynaptic terminal. C. The neurotransmitter being released by the presynaptic cell. D. The receptor present in the postsynaptic cell E. The type of postsynaptic cell.

D. The receptor present in the postsynaptic cell

Which of the following statements about the functional anatomy of the brain is incorrect? A. The occipital lobe processes visual information originating from the retina. B. The central sulcus separates the frontal lobe from the parietal lobe. C. The hippocampus is critically involved in the formation of episodic memories. D. The symptoms of Parkinson's disease--rigidity, slowness of movement, and resting tremor-- are caused by degeneration of the cerebellum. E. All of them are correct.

D. The symptoms of Parkinson's disease--rigidity, slowness of movement, and resting tremor-- are caused by degeneration of the cerebellum.

All of the following statements about voltage-sensitive calcium channels are true EXCEPT: A. are essential for chemical neurotransmission. B. are opened by the arrival of an action potential at the axon terminal. C. allow the entry of calcium ions into the presynaptic terminal. D. They are necessary for the firing of action potentials at the nodes of Ranvier. E. All of the statements are true.

D. They are necessary for the firing of action potentials at the nodes of Ranvier.

14) What would happen to the membrane potential of a cell that is permeable only to K+ if the extracellular concentration of K+ suddenly decreased by 50%? A. it would depolarize B. there would be no change C. it would hyperpolarize and then depolarize D. it would hyperpolarize E. There is not enough information to answer this question.

D. it would hyperpolarize

Most of the energy that the brain expends is used for A. producing action potentials. B. synthesizing and releasing neurotransmitters. C. saltatory conduction. D. maintaining / restoring ionic gradients. E. Integrating information.

D. maintaining / restoring ionic gradients.

which of the following is a characteristic of the endocrine system? A. the speed of response is generally rapid B. it coordinate rapid, precise responses,\ C. its chemical messengers travel very short distances D.the duration of action is generally prolonged E. its specificity of action is dependent a close anatomical relationship

D. the duration of action is generally prolonged

A 65 year old man is suffering from congestive heart failure. He has cardiac output of 4L/min, arterial pressure of 115/85mmHg and a heart rate of 90 beats/min. Further tests reveal that the patient has a right atrial pressure of 20 mmHg (normal Right Atrial Pressure is ~0mmHg). An increase in which of the following would be expected in this patient so he can stay alive? A) Plasma colloid osmotic pressure. B) Interstitial colloid osmotic pressure. C) Arterial pressure D) Cardiac output E) Vena cava pressure.

E) Vena cava pressure.

Which of the following would decrease the rate of diffusion? A. increasing the temp. B. Increasing the size of the diffusing solute C. increasing the concentration gradient D.increasing the surface area for diffusion E. All of the above would increase rate of diffusion

E. All of the above would increase rate of diffusion

Which of the following would increase the rate of diffusion? A. Increasing the temperature B. Decreasing the size of the diffusing solute C. Increasing the concentration gradient D. Increasing the surface area for diffusion E. All of the choices would increase the rate of diffusion

E. All of the choices would increase the rate of diffusion

Adaptation in sensory receptors A. Refers to the decrease or cessation of receptor potentials despite maintenance of a stimulus B. Occurs to the same extent in all receptors C. May be rapid or slow, depending on the receptor D. Both A and B is correct. E. Both A and C are correct.

E. Both A and C are correct.

We can see "yellow" when A. Yellow cones are activated. B. Blue cones are inhibited. C. Red cones are inhibited. D. Red, blue, and green cones are activated. E. Both red and green cones are activated.

E. Both red and green cones are activated.

A person who has trouble balancing on one feet but can walk somewhat normally most likely has damage to the: A. temporal lobe. B. parietal lobe. C. occipital lobe. D. frontal lobe. E. cerebellum.

E. Cerebellum

Tetrodotoxin (TTX) is a toxin that blocks voltage-gated Na+ channels. What effect does this toxin have on the properties of action potentials? A. It increases their duration. B. It increases their amplitude. C. It increases their frequency. D. It increases their conduction velocity down axons. E. None of the above.

E. None of the above.

The rising phase of an action potential is associated with... A. The opening of voltage -gated Na+ channels and the eflux of Na+ from the cell B. The opening of voltage -gated K+ channels and the eflux of K+ from the cell C. An increase in the number of leak Na+ channels that are open. D. An increase in the driving force for Na+ E. None of the answer are correct.

E. None of the answer are correct.

EVERYONE GOT CREDIT. The motor homunculus A. is located in the somatosensory cortex. B. overrepresents regions with low acuity. C. overrepresents regions with high acuity. D. represents a map of brain areas dedicated to sensory processing for different anatomical divisions of the body. E. None of these answers are correct.

E. None of these answers are correct.

Which of the following changes would reduce the length of the refractory period (and thus allow a second action potential to take place more quickly)? A. Increasing the time it takes to open and close voltage gated K+ channels. B. Increasing the number of leak K+ channels. C. Replacing the normal voltage gated K+ channels with voltage gated K+ channels that do not inactivate. D. Making threshold more positive. E. None of these changes would impact the length of the refractory period

E. None of these changes would impact the length of the refractory period

Hormonal secretion is characterized by: A. local chemical messengers that are released into the extracellular environment act on nearby cells B. ions and small molecules that are directly exchanged without entering the extracellular space C. specialized cell surface markers that link cells expressing compatible markers D. local chemical messengers that are released in response to electrical signals and act locally on an adjoining cell E. chemical messengers that are released into the blood and act at receptors in distal tissues

E. chemical messengers that are released into the blood and act at receptors in distal tissues

The majority of glucose enters cells through: A. Simple Diffusion through the lipid bilayer B. Channels C. Active Transport D. Facilitated Diffusion E. Pumps F. Both C & D

F. Both C & D

How many ATP molecules are used for each cross bridge cycle? (hint: splitting of ATP energizes the cross bridge and binding of ATP to myosin allows detachment of the cross bridge from actin.)

One ATP molecule is used for each cross-bridge cycle.

What are the three roles of ATP in skeletal muscle contraction?

Power stroke of the myosin cross bridge Disconnecting the cross bridge from thin filaments Ca2+ uptake by the sarcoplasmic reticulum

Which of the following is/are true about this neuron? A. The neuron will have a negative resting potential. B. The neuron's resting potential will still be aprox. -122mV. C. The neuron's resting potential will be mostly dominated by the K- ion. D. A and B are correct. E. None of the answers are correct.

You are working with a neuron from a recently identified organism who has up to now shown to have very different properties to those of mammalian neurons: • The cell membrane of this neuron is only permeable to Cl- ions at rest. • The normal concentration of Cl- inside the cell is 100mM and outside the cell, it is 1mM. E.none are correct

The thalamus a) performs preliminary processing of sensory input on its way to the cortex. b) inhibits muscle tone throughout the body. c) controls thirst, urine output, and food intake. d) plays a role in emotional and behavioral patterns. e) selects and maintains purposeful motor activity while suppressing useless or unwanted patterns of movement.

a) performs preliminary processing of sensory input on its way to the cortex.

During a competitive fencing match your opponent's face guard shifts slightly and you accidentally pierce the base of his skull with your saber. He is rushed to the emergency room and given a magnetic resonance image to determine what part of his brain has been injured. The neurologist finds that the right optic tract has been severed. What form of visual field deficit does he have as a result of the accident? a. a complete loss of vision in the left visual field of both eyes. b. a complete loss of vision in the right visual field of both eyes. c. a complete loss of vision in the upper visual field of the left eye and the lower visual field of the right eye. d. a complete loss of vision in the left visual field of the left eye and the right visual field of the right eye. e. a complete loss of vision in the right eye

a. a complete loss of vision in the left visual field of both eyes.

In skeletal muscle, a motor unit is defined as: a. a motor neuron and all of the muscle fibers it innervates. b. a muscle fiber and all of the motor neurons that innervate it. c. a sarcomere and all of the actin and myosin filaments contained within it. d. a myofibril and all of its sarcomeres connected end to end.

a. a motor neuron and all of the muscle fibers it innervates.

The smaller the receptive fields in a region, the a) greater the density of receptors in the region. b) greater the acuity in the region. c) more cortical space allotted for sensory reception from the region. d) All of these answers.

d) All of these answers.

Tetanus is a debilitating medical condition that can be contracted via a wound contaminated with the bacteria Clostridium tetani. The major symptom of tetanus is muscle stiffness and rigidity. This stiffness and rigidity results from the tetanus toxin a) blocking voltage-gated Na+ channels in the plasma membrane of muscle cells. b) blocking the release of inhibitory neurotransmitter from interneurons within the spinal cord. c) blocking the release of excitatory neurotransmitter from interneurons within the spinal cord. d) exciting spinocerebeller axons. e) inhibiting activity in motor cortex.

b) blocking the release of inhibitory neurotransmitter from interneurons within the spinal cord.

Afferent fibers carrying touch information from Pacinian corpuscles enter the spinal cord a) via the ventral horn on the side of the spinal cord closest to the cell bodies of the afferent fibers. b) via the dorsal horn on the side of the spinal cord closest to the cell bodies of the afferent fibers. c) via the ventral horn on the side of the spinal cord away from the cell bodies of the afferent fibers. d) via the dorsal horn on the side of the spinal cord away from the cell bodies of the afferent fibers.

b) via the dorsal horn on the side of the spinal cord closest to the cell bodies of the afferent fibers.

Within the somatosensory cortex of humans, there is an over-representation of the body surface corresponding to the a. legs b. face c. back d. abdomen e. arms

b. face

Which of the following statements concerning the characteristics of different types of muscle fibers is incorrect? a. the higher the ATPase activity, the faster the speed of contraction. b. muscles that have high glycolytic capacity and large glycogen stores are more resistant to fatigue. c. muscles with high ATP-synthesizing ability are more resistant to fatigue. d. oxidative types of muscle fibers contain myoglobin. e. muscle fibers containing large amounts of myoglobin have a dark red color in comparison to the paler fibers, which have little myoglobin.

b. muscles that have high glycolytic capacity and large glycogen stores are more resistant to fatigue.

The T tubules a. store Ca2+. b. provide a means of rapidly transmitting the action potential from the surface into the central portions of the muscle fiber. c. store ATP. d. have expanded lateral sacs. e. Both store Ca2+ and have expanded lateral sacs.

b. provide a means of rapidly transmitting the action potential from the surface into the central portions of the muscle fiber.

Which of the following statements about smooth muscle is false? a. smooth muscle is often found in the walls of hollow organs and tubes such as blood vessels and the intestines. b. smooth muscle is striated. c. smooth muscle contains thin filaments that slide relative to stationary thick filaments in response to a rise in cytosolic Ca++. d. smooth muscle lacks the transverse (T) tubule organization that is characteristic of skeletal muscle. e. none of the above statements are false.

b. smooth muscle is striated.

The symptoms of Parkinson's disease--rigidity, slowness of movement, and resting tremor-- are caused by degeneration of a specific population of cells in the central nervous system. In which location are the affected (degenerating) cells located? a) the cerebellum b) the motor cortex c) the basal ganglia d) the spinal cord e) the thalamus

c) the basal ganglia

During muscle contraction, the a. actin proteins contract. b. A band becomes shorter. c. H zone becomes smaller or disappears. d. I band remains unchanged. e. More than one of these answers.

c. H zone becomes smaller or disappears.

Which of the following does not occur in a photoreceptor during exposure to light? a. membrane hyperpolarization. b. closure of Na+ channels in the outer segment. c. increased transmitter release from the synaptic terminal. d. decrease in cyclic GMP in the outer segment. e. closure of Ca2+ channels in the synaptic terminal.

c. increased transmitter release from the synaptic terminal.

A function of tropomyosin is a. bind Ca2+. b. form attachments with myosin cross bridges. c. prevent myosin cross bridges from attaching to the thin filaments. d. serve as an ATPase. e. None of these answers.

c. prevent myosin cross bridges from attaching to the thin filaments.

Which of the following is not involved in the relaxation of muscle? a. when acetylcholine is destroyed by acetylcholinesterase. b. when there is no longer a local action potential. c. when the T tubules actively take up the Ca2+ that had been released. d. when the actin and myosin molecules are no longer bound together. e. when the troponin-tropomyosin complex slips back into its blocking position.

c. when the T tubules actively take up the Ca2+ that had been released.

Which of the following best describes the anatomical pathway mediating visual perception? a) (primary visual cortex) - (photoreceptor) - (ganglion cell) - (bipolar cell) - (lateral geniculate nucleus) - (extrastriate visual cortex) b) (ganglion cell) - (photoreceptor) - (bipolar cell) - (lateral geniculate nucleus) - (primary visual cortex) - (extrastriate visual cortex) d) (photoreceptor) - (bipolar cell) - (ganglion cell) - (lateral geniculate nucleus) - (primary visual cortex) - (extrastriate visual cortex) e) (bipolar cell) - (ganglion cell) - (photoreceptor) - (lateral geniculate nucleus) - (primary visual cortex) - (extrastriate visual cortex)

d) (photoreceptor) - (bipolar cell) - (ganglion cell) - (lateral geniculate nucleus) - (primary visual cortex) - (extrastriate visual cortex)

Phineas Gage had the misfortune of piercing his prefrontal association cortex with a tamping iron that was 3 feet 7 inches long and weighed 13.5 pounds. Although he survived the accident, he displayed several behavioral deficits. Which group of deficits best matched those displayed by Phineas Gage? a) difficulty regulating emotional responses (particularly fear) b) inability to form new memories, difficulty with spatial guidance c) lack of attention to the left side of his body, unable to recognize faces d) socially unacceptable behavior, lack of planning, personality changes

d) socially unacceptable behavior, lack of planning, personality changes

Vision mediated by rods a. is more sensitive to low light levels than cone-mediated vision. b. has low acuity than cone-mediated vision. c. provides vision in shades of gray. d. All of these answers.

d. All of these answers.

High-frequency sound elicits maximal vibration of the basilar membrane a. away from the oval window where the basilar membrane is stiff and narrow. b. near the oval window where the basilar membrane is wide and flexible. c. away from the oval window where the basilar membrane is wide and flexible. d. near the oval window where the basilar membrane is stiff and narrow.

d. near the oval window where the basilar membrane is stiff and narrow.

The corpus callosum interconnects the a. brain stem and cerebellum b. brain stem and diencephalon c. hypothalamus and thalamus d. two cerebral hemispheres e. cerebellum and spinal cord

d. two cerebral hemispheres

Auditory functions of the cerebral cortex are localized in a. the parietal lobes b. the frontal lobes c. the occipital lobes d. the limbic lobes e. the temporal lobes

e. the temporal lobes

Explain the differences between isometric contraction and isotonic contraction.

isotonic contraction = muscle changes length while the load remains constant. Isometric contraction = muscle develops tension but does not shorten or lengthen.