Anatomy and Physiology Chapter 11

Which functions are controlled through the autonomic nervous system? 1. blood pressure 2. heart rate 3. water balance 4. temperature regulation

1,2,3,4

Acetylcholinesterase (AChE) inhibitor administration is a common treatment for myasthenia gravis. Why does this help alleviate some of the symptoms of this autoimmune disease?

AChE inhibition increases ACh in the synaptic cleft to bind remaining ACh receptors

What would be the effect of ACh binding to its receptor on the postsynaptic muscle cell?

Na+ would flow into the cell and K+ would flow out of the cell

The motor end plate is

a folded area of muscle cell membrane with ACh receptors clustered at the top of each fold

Ganglion

a location outside of the CNS where autonomic signals can synapse

Preganglionic autonomic neuron

a neuron that delivers an action potential from the CNS to another neuron in the PNS

Somatic motor neuron

a neuron that delivers an action potential from the central nervous system to a skeletal muscle

Postganglionic autonomic neuron

a neuron that receives an action potential from another neuron and then delivers that action potential to a smooth muscle

What is a varicosity in the autonomic nervous system?

a series of swollen ends that act as synapses

Neurons in the parasympathetic pathway use which of the following neurotransmitters?

acetylcholine

Somatic motor neurons secrete the neurotransmitter ________ onto ________ receptors at the target tissue.

acetylcholine; nicotinic

In the autonomic nervous system, neurotransmitter activation of its receptor terminates when the neurotransmitter is metabolized by enzymes in the extracellular fluid, or when it diffuses away. Which other mechanism leads to termination of neurotransmitter activity?

active transport into surrounding cells

Match the following with its description. A. acetylcholine B. norepinephrine C. cholinergic nicotinic receptor D. adrenergic receptor E. cholinergic muscarinic receptor sympathetic tissue receptor

adrenergic receptor

Which of the following is an effect of the parasympathetic nervous system?

airway constriction

The two varieties of adrenergic receptors are

alpha and beta

Neurotransmitters of norepinephrine

alpha-1; beta-1

Which area is NOT normally considered to be an autonomic control center?

amygdala

What is the trigger for ACh release into the synaptic cleft of a neuromuscular junction?

an action potential at the axon terminal opens voltage-gated Ca2+ channels

Antagonistic control of efferent output is typical of the ________ division.

autonomic

The division of the efferent nervous system that controls smooth and cardiac muscles and many glands is the ________ division

autonomic

Cholinergic nicotinic receptors are found in the ________ of the ANS.

autonomic ganglia

The diameter of bronchioles varies under the control of ________ neurons, which cause the diameter to _______

autonomic; constrict under parasympathetic control and dilate under sympathetic control

Which of the following best describes the direction and function of efferent signals?

away from the central nervous system, cause motor effects in glands or muscles

Neurotransmitters of epinephrine

beta-1; beta-2

Muscarine, a chemical produced by certain mushrooms, binds to muscarinic receptors mimicking the effect of acetylcholine. How do you think administering this chemical would change body function? The drug would _____________.

change the functionality of the smooth muscles within the digestive system; change the functionality of the heart; change the functionality of certain exocrine and endocrine glands

Match the following with its description. A. acetylcholine B. norepinephrine C. cholinergic nicotinic receptor D. adrenergic receptor E. cholinergic muscarinic receptor parasympathetic tissue receptor

cholinergic muscarinic receptor

Match the following with its description. A. acetylcholine B. norepinephrine C. cholinergic nicotinic receptor D. adrenergic receptor E. cholinergic muscarinic receptor target receptor for preganglionic neurons

cholinergic nicotinic receptor

Sometimes the effects of sympathetic stimulation can be contradictory in the same types of tissue. For example, in the arterioles of the GI tract, sympathetic stimulation causes constriction while arterioles of skeletal muscle can dilate in response to sympathetic stimulation. What mechanism explains these opposite effects?

different receptors for the same neurotransmitter

Increased parasympathetic stimulation

increases gastric motility

The adrenal medulla is important to the sympathetic branch of the autonomic nervous system because

it is a source of catecholamines, it is considered a modified sympathetic ganglion, and it releases epinephrine and norepinephrine directly into the blood

Which statements apply to the parasympathetic division of the nervous system?

it is dominant during "resting and digesting" and its ganglia are nearby, on or near their target organs

Why is the parasympathetic nervous system also called the cranio-sacral division?

its nerves arise in the head and sacrum

What is an appropriate classification for the ACh receptor found in the neuromuscular junction?

ligand-gated; nonspecific; cation channel

What is the main enzyme responsible for the breakdown of catecholamines?

monoamine oxidase

________ postganglionic sympathetic neurons secrete ________ onto their target cells

most; norepinephrine

The neurotransmitter that controls skeletal muscle causes which of the following?

muscle contraction

Neurotransmitters of acetylcholine

nicotinic; muscarinic

The somatic nervous system and the parasympathetic nervous system both release acetylcholine (ACh) onto their target tissues. Do you predict that this would indicate that these two pathways carry out the same effects? Why or why not?

no because the receptors found on the target tissue for each pathway are different

Match the response with the type of chemical. A. sympathetic antagonist B. parasympathetic antagonist blocks secretion of pancreatic enzymes

parasympathetic antagonist

Cholinergic muscarinic receptors are found at the ________ in the ANS.

parasympathetic neuroeffector junctions

Which of the following are components of the efferent nervous system?

parasympathetic neurons; somatic motor neurons; and sympathetic neurons

Acetylcholine (Ach) site of release

postganglionic and preganglionic neurons from the parasympathetic nervous system; somatic motor neuron; preganglionic neuron from the sympathetic nervous system

Which of the following has its cell body in the ganglion?

postganglionic neuron

Norepinephrine (NE) site of release

postganglionic neuron from the sympathetic nervous system

Which of these characteristics is the same in both the sympathetic and parasympathetic branches for the vast majority of neurons?

preganglionic neurotransmitter

The target tissue(s) of somatic motor neurons is/are ______

skeletal muscle

Which of the following is/are targets of the efferent nervous system?

skeletal muscle; smooth muscle; cardiac muscle; and glands

A single neuron is stimulated at the central nervous system; this signal travels all the way to the target tissue, where the neurotransmitter acetylcholine is released onto the target tissue. The acetylcholine binds to a nicotinic receptor to induce skeletal muscle contraction. These steps describe the function of which branch of the efferent nervous system?

somatic

The two divisions of the efferent side of the peripheral nervous system are

somatic motor neurons and autonomic neurons

Match the response with the type of chemical. A. sympathetic agonist B. parasympathetic agonist pupil dilation

sympathetic agonist

Match the response with the type of chemical. A. sympathetic antagonist B. parasympathetic antagonist blocks sweating

sympathetic antagonist

The division of the autonomic nervous system that prepares the body for intense levels of activity and stress is the

sympathetic division

Which pathways make up the autonomic nervous system?

sympathetic pathways; parasympathetic pathways; and adrenal sympathetic pathways

The diameter of blood vessels varies under the control of ________ neurons, which cause the diameter to ________.

sympathetic; either increase or decrease, depending upon the type of receptor present

Which nervous system division has parasympathetic and sympathetic branches?

the autonomic division of the efferent nervous system

Sympathetic pathways originate in which region of the spinal cord?

thoracic and lumbar

Match the answers to the questions. A. true only for the sympathetic division B. true only for the parasympathetic division C. true for both divisions The cell bodies of preganglionic neurons are found either in the brain stem or in the sacral region of the spinal cord.

true only for the parasympathetic division

Match the answers to the questions. A. true only for the sympathetic division B. true only for the parasympathetic division C. true for both divisions The neurotransmitter acetylcholine is released by neurons at the neuroeffector synapse.

true only for the parasympathetic division

Match the answers to the questions. A. true only for the sympathetic division B. true only for the parasympathetic division C. true for both divisions It releases norepinephrine at the neuroeffector synapse.

true only for the sympathetic division

The ________ is the major source of parasympathetic output.

vagus nerve

________ are swellings that contain vesicles filled with neurotransmitters

varicosities