Revision Questions for Lectures

FINAL REVISION QUESTIONS FOR ACADEMIC YEAR 2010-2011

PNE-Efferent Division

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Identify the letter of the choice that best completes the statement or answers the question.

____ 1. The autonomic nervous system is

part of the somatic nervous system.

considered to be the involuntary branch of the efferent division of the peripheral nervous system.

part of the central nervous system.

Two of these answers.

All of these answers.

____ 2. The overall functioning of the contributes to

conservation of energy resources when stress levels are low.

mobilization of energy reserves when stress levels are high.

suppression of nonvital activities when stress levels are high.

homeostasis.

All these answers.

____ 3. Which one of the following involves a response of a skeletal muscle through an efferent output?

augmented breathing from the diaphragm

delayed emptying of the stomach

increased pumping of blood

increased secretion of insulin

initiation of sweating

____ 4. Which is not characteristic of sympathetic pathways?

fibers issue from the thoracic and lumbar levels.

preganglionic fibers release norepinephrine.

postganlionic fibers release ACh.

short preganglionic fibers.

most preganglioic fibers synapse in the chain ganglia.

____ 5. Parasympathetic postganglionic fibers

arise from the ganglion chain located along either side of the spinal cord.

are cholinergic.

secrete norepinephrine.

Both (a) and (b) above.

Both (a) and (c) above.

____ 6. All of the following release acetylcholine except

sympathetic preganglionic fibers.

parasympathetic preganglionic fibers.

sympathetic postganglionic fibers.

parasympathetic postganglionic fibers.

motor neurons.

____ 7. Postganglionic autonomic fibers

end in a single terminal swelling, like a synaptic knob, that releases the neurotransmitter.

have numerous varicosities in their terminal branches that simultaneously release neurotransmitter over a large area of the innervated organ rather than on single cells.

innervate skeletal, smooth, and cardiac muscle.

Both (a) and (c) above.

Both (b) and (c) above.

____ 8. What system would suppress the digestive organs during times of greater physical activity?

sympathetic.

parasympathetic.

enteric nervous system.

somatic nervous system.

None of these answers.

____ 9. The sympathetic nervous system

is always excitatory.

innervates only tissues concerned with protecting the body against challenges from the outside environment.

dominates in fight-or-fight situations.

is part of the somatic nervous system.

is part of the afferent division of the peripheral nervous system.

____ 10. The sympathetic nervous system

is part of the somatic nervous system.

has cholinergic preganglionic and adrenergic postganglionic fibers.

originates in the thoracic and lumbar regions of the spinal cord.

Both (b) and (c) above.

All of these answers.

____ 11. Which of the following does not characterize the sympathetic nervous system?

It promotes responses that prepare the body for strenuous physical activity.

It is part of the autonomic nervous system.

It has norepinephrine as its postganglionic neurotransmitter.

It is always excitatory (that is, it increases the activity in every tissue it innervates).

It is part of the efferent division of the peripheral nervous system.

____ 12. Select the incorrect statement about the parasympathetic nervous system.

It signals cardiac muscle and smooth muscle.

Its postganglionic fibers release norepinephrine.

Its preganglionic fibers release ACh.

Part of it originates in the brain.

Part of it originates in the sacral region of the spinal cord.

____ 13. Which of the following statements concerning the terminal ganglia is correct?

long parasympathetic preganglionic fibers end on the terminal ganglia, which lie in or near the effector organ.

terminal ganglia give rise to sympathetic postganglionic fibers.

terminal ganglia are the final common pathway for the autonomic nervous system.

the terminal ganglia contain muscarinic receptors.

terminal ganglia lie in a chain located along either side of the spinal cord.

____ 14. The parasympathetic nervous system

has long preganglionic fibers that end on terminal ganglia, which lie in or near the effector organ.

dominates in quiet, relaxed situations.

releases a postganglionic neurotransmitter that binds with muscarinic receptors.

Both (a) and (b) above.

All of these answers.

____ 15. Sympathetic stimulation ________ heart rate and _________ the motility in the digestive tract.

does not affect, decreases.

decreases, decreases.

decreases, increases.

increases, decreases.

increases, increases.

____ 16. Parasympathetic stimulation _________ heart rate and ________ the motility in the digestive tract.

does not affect, increases.

decreases, decreases.

decreases, increases.

increases, decreases.

increases, increases.

____ 17. Which organ is not innervated by the parasympathetic division?

blood vessels.

inte.stines.

eye.

liver.

erectile tissues.

____ 18. Nicotinic receptors

bind with acetylcholine released from parasympathetic postganglionic fibers.

respond to acetylcholine released from both sympathetic and parasympathetic preganglionic fibers.

are found primarily in the heart.

bind with norepinephrine released from sympathetic postganglionic fibers.

None of these answers.

____ 19. Atropine __________ the effect of acetylcholine at _________ receptors and __________ __________ receptors.

blocks, muscarinic, does not affect, nicotinic.

enhances, muscarinic, does not affect, nicotinic.

blocks, nicotinic, does not affect, muscarinic.

enhances, nicotinic, does not affect, muscarinic.

blocks, muscarinic, enhances, nicotinic.

____ 18. The neurotransmitter at the neuromuscular junction is

acetylcholine.

the same as the transmitter substance at parasympathetic postganglionic nerve endings.

the same as that released by all preganglionic fibers.

Both (a) and (b) above .

All of these answers .

____ 19. Which statement characterizes sympathetic activity?

blood vessels with alpha receptors dilate.

the bronchioles constrict.

the pupils of the eye dilate.

the secretion of the sweat glands is inhibited.

the urinary bladder contracts and eliminates urine.

____ 20. Acetylcholinesterase

has enhanced activity from organophosphates.

inactivates a neurotransmitter.

is a neurotransmitter.

stimulates an excitatory postsynaptic potential.

triggers the release of sodium into postsynaptic cells.

____ 21. The motor end plate

contains receptor sites that are capable of binding curare.

contains acetylcholinesterase.

experiences an increase in permeability to cations when combined with acetylcholine.

Both (b) and (c) above .

All of these answers .

____ 22. The neuromuscular junction

is the junction between a motor neuron and a skeletal muscle fiber.

transmits an action potential between the nerve cell and muscle cell on a one-to-one basis.

may produce either an EPSP or an IPSP on the motor end plate.

Both (a) and (b) above .

All of these answers .

____ 23. Which of the following is the final signaling step following impulse conduction along the axon terminal?

ACh binds with receptors on the muscle cell membrane, opening sodium channels.

ACh diffuses across the cleft of the junction.

ACh is released by exocytosis.

calcium diffuses into the terminal button.

voltage-gated channels for calcium are opened.

____ 24. Which type of receptor binds norepinephrine on cardiac muscle, thus increasing cardiac activity?

cholinergic.

nicotinic.

alpha.

beta1.

beta2.

____ 25. Acetylcholine

is released from an axon.

destroys acetylcholinesterase.

is blocked by sodium.

Both (a) and (b) above .

All of these answers .

____ 26. Acetylcholine

is released from the vesicles when an action potential is propagated to the terminal button of a motor neuron.

increases the permeability of the motor end plate to Na⁺ and K⁺ when combined with the receptor sites on the motor end plate.

is the chemical transmitter substance at the neuromuscular junction.

Two of these answers .

All of these answers .

____ 27. What is the fate of ACh following binding to receptors?

it remains bound causing continued excitement.

it is removed by the enzyme acteylcholinesterase.

it is actively reabsorbed the axon terminal.

it is passively reabsorbed by the muscle cell.

None of these answers.

____ 28. What would occur if ACh was not removed from the nicotinic receptors on skeletal muscle cells?

the cell would relax.

the cell would repolarize with the opening of chloride channels.

the cell would remain contracted until fatigued.

sodium would continue to move into the cell causing excitation.

Both (c) and (d) above.

____ 29. An EPP

occurs because of Na⁺ movement inward at the motor end plate region as a result of permeability changes induced by binding of acetylcholine with end-plate receptor sites.

is usually smaller in magnitude than an EPSP.

is terminated when Ca²⁺ inactivates acetylcholine.

Both (a) and (b) above.

All of these answers.

____ 30. Select the correct statement about efferent neurons.

their cell bodies are located in dorsal root ganglia.

they are part of a two-neuron chain in the autonomic nervous system.

they arise peripherally at a receptor.

they send information toward the central nervous system.

they signal only skeletal muscles.

____ 31. Select the CNS structure(s) that can influence autonomic activity.

medulla.

hypothalamus.

spinal cord.

Both (a) and (b) above.

All these answers.

____ 32. Which of the following chemicals paralyzes skeletal muscle by binding to the acetylcholine receptor sites?

black widow spider venom.

curare.

organophosphates.

DDT.

local anesthetics.

____ 33. Curare

strongly binds to acetylcholine receptor sites.

inhibits acetylcholinesterase.

is found in pesticides and military nerve gases.

Two of these answers.

All of these answers.

____ 34. Select the correct statement about the neuromuscular junction.

AChE activity is absent here.

It involves presynaptic neurons of the autonomic nervous system.

It is a junction between two neurons.

It is always excitatory.

The axon terminals do not store neurotransmitters.

____ 35. Atropine is an antagonist of ACh, it works by

selectively binding to nicotinic receptors.

selectively binding to muscarinic receptors.

Blocking the binding of ACh.

Both (a) and (b) above

Both (b) and (c) above.

GOOD LUCK

Dr. Salah A. Martin

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