Exam 7: The Peripheral Nervous System: Efferent Division

Most innervated blood vessels receive only sympathetic nerve fibers.

Use this figure to answer the following questions. Which neuron releases a neurotransmitter that binds to B₂ receptors? a. 1 and 5 only b. 3 and 4 only c. 3 only d. 5 only e. 1, 3, and 5

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

Sequencing Indicate the proper sequence of events at the neuromuscular junction by filling in the blank with the appropriate number from 2 through 7. Numbers 1 and 8 are already identified. \begin{array}{|l|l|}\hline &\text {AChis released from the axon terminal by exocytosis. } \\\hline &\text {AnEPP takes place, primarily as a result of \mathrm{Na} influx. } \\\hline 8 &\text {A cetylcholinesterase inactivates \( \mathrm{ACh} \), terminating activity at the neuromuscular junction } \\\hline 1&\text {An action potential is propagated to an axon terminal of a motor neuron } \\\hline &\text {Channels that permit passage of \( \mathrm{Na}^{+} \)and \( \mathrm{K} \) are opened in the motor end plate. } \\\hline &\text {\( \mathrm{Ca}^{2+} \) channels are opened in the axon terminal. } \\\hline &\text {Local current flow between the motor end plate and adjac ent mus de-cell membrane initiates an action potential that spreads } \\&\text { throughout the muscle fiber. }\\\hline &\text {ACh binds with receptor sites on the motor end plate. } \\\hline \end{array}

Describe the events that occur at a skeletal neuromuscular junction. Include the following in your

The salivary glands and the eye are sympathetically innervated by cranial nerves.

Parasympathetic postganglionic fibers

The autonomic nervous system mainly controls smooth and cardiac muscles, but it can inhibit a few skeletal muscles.

Action potentials are transmitted on a one-to-one basis at both a neuromuscular junction and a synapse.

What are the various ways in which toxins can interfere with normal neuron functioning?

The sympathetic nervous system

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

The sympathetic postganglionic fibers that innervate the sweat glands secrete acetylcholine rather than norepinephrine.

Use this figure to answer the following questions. The axons labeled 1 would release ____ and have a(n) ____ effect on the effector organ. a. ACh; inhibitory b. ACh; excitatory c. NE; inhibitory d. NE; excitatory e. NE; inhibitory and ACh; excitatory

Most innervated blood vessels receive sympathetic and parasympathetic fibers.

Complete each of the following statments. Most sympathetic postganglionic fibers secrete the neurotransmitter ____________________, whereas all parasympathetic postganglionic fibers secrete the neurotransmitter ____________________.

Muscarinic receptors are found on the effector cells innervated by the sympathetic division.

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

Use this figure to answer the following questions. Neuron 2 a. uses adrenergic receptors to respond to stimulation by a preganglionic neuron b. releases NE onto a very short postganglionic neuron c. releases a chemical that binds to adrenergic receptors on a postganglionic neuron d. all of these e. none of these

Use this figure to answer the following questions. Identify the correct statement(s): a. Neuron 5 causes contraction of its effector. b. Neuron 6 is stimulated by ACh released from a preganglionic neuron. c. Neuron 1 causes constriction of bronchioles d. Neuron 2 releases a chemical that binds to nicotinic receptors on a postganglionic neuron. e. Two of the above.