Chapter 14 Part 1 - Autonomic Nervous System

Preparing the body for the "fight-or-flight" response is the role of the ________. -somatic nervous system -sympathetic division -cerebrum -parasympathetic division

Sympathetic division. The sympathetic division mobilizes the body during activity. -constricts visceral blood vessels, shunting blood to active skeletal muscles & rapidly beating heart. -dialates the bronchioles in the lungs, increasing air flow. -stimulates liver to release more glucose into the blood to accommodate the increased energy needs of body cells.

The "fight or flight" division of the autonomic nervous system is the ________. -sympathetic division -somatic division -peripheral division -parasympathetic division

Sympathetic division. The sympathetic division temporarily reduces nonessential acitivities. i.e. surpressing energy use in GI tract.

Which of these effectors is NOT directly controlled by the autonomic nervous system? -cardiac muscle -most glands -skeletal muscle -smooth muscle

The ANS does not directly control skeletal muscle. The somatic nervous system stimulates skeletal muscles.

Which of the following does NOT describe the ANS? -general visceral motor system -a system of motor neurons that innervates all muscle cells -a system of motor neurons that innervates smooth and cardiac muscle and glands -involuntary nervous system

The ANS is not a system of motor neurons that innervates all muscle cells. The ANS innervates cardiac and smooth muscle and glands.

True or False The craniosacral division is another name for the parasympathetic division.

True. Parasympathetic fibers are craniosacral - they originate from the brain (cranium) and sacral spinal cord. Sympathetic fibers are thoracolumbar - they originate in the thoracic and lumbar regions of the spinal cord.

True or False? Autonomic ganglia are motor ganglia, containing the cell bodies of motor neurons.

True. The somatic motor division lacks ganglia entirely.

The route of major parasympathetic outflow from the head is via the ________. -sacral nerves -phrenic nerve -vagus (X) nerves -sympathetic trunk

Vagus (X) nerves. The vagal nerve fibers (preganglionic axons) arise mostly from the dorsal motor nuclei of the medulla (medulla oblongata) and then synapse in terminal ganglia located in walls of the target organ.

The smooth muscle of the digestive viscera is served largely by the ________. -vagus (X) nerves -pelvic nerves -lumbar splanchnic nerves -cephalic plexus

Vagus (X) nerves. The vagus nerves innervate the liver, gallbladder, stomach, small intestine, pancreas, and the proximal half of the large intestine.

Over 90% of all parasympathetic fibers are derived from cranial nerve ________. -V (trigeminal) -X (vagus) -XII (hypoglossal) -VII (facial)

X (vagus) They provide fibers to the neck and to nerve plexuses (interweaving networks of nerves) that serve virtually every organ in the thoracic and abdominal cavities. They also contain fibers from both the parasympathetic and sympathetic divisions.

The parasympathetic fibers of the ________ nerve stimulate many large glands in the head such as the nasal and lacrimal glands. -optic (II) -oculomotor (III) -trochlear (IV) -facial (VII)

Facial (VII) Fibers that activate the nasal glands and the lacrimal glands of the eyes originate in the lacrimal nuclei of the pons.

True or False? The autonomic and somatic nervous systems are two separate systems that work totally independent of each other and lack any functional overlap.

False. Most of the body's adaptions to changing internal and external conditions involve both skeletal muscles and visceral organs. -i.e: when skeletal muscles are working hard, they need more oxygen and glucose, so autonomic control mechanisms speed up heart rate and dilate airways to meet these needs and maintain homeostasis.

True or False The facial (VII), glossopharyngeal (IX), and vagus (X) nerves contain postganglionic fibers of the parasympathetic nervous system.

False. Preganglionic fibers run in the oculomotor, facial, glossopharyngeal, and vagus cranial nerves.

True or false? The ANS stimulates smooth muscles, skeletal muscles and glands, whereas the somatic nervous system innervates skeletal muscles only.

False. The ANS innervates cardiac and smooth muscle and glands, the somatic nervous system stimulates skeletal muscles.

True or False? The sympathetic and parasympathetic divisions of the ANS have the same effect on most body organ systems.

False. The effect may be excitatory or inhibitory, depending on the type of receptors on the target organ.

True or False All splanchnic nerves are sympathetic.

False. The sacral part of the parasympathetic division contains the pelvic splanchnic nerves, which pass through the inferior hypogastric (pelvic) plexus in the pelvic floor.

Which of the following is NOT a plexus of the vagus (X) nerve? -cardiac -inferior hypogastric -pulmonary -esophageal

Inferior hypogastric. Cardiac- supplies fibers to the heart that slow heart rate. Pulmonary- serves airways of the lungs. Esophageal- serves the esophagus and part of the stomach.

Autonomic ganglia contain ________. -the cell bodies of motor neurons -synapses between postganglionic fibers and their effectors -an outer connective tissue capsule around the cell bodies of preganglionic motor neurons -both somatic afferent and efferent neurons

The cell bodies of motor neurons. The postganglionic neuron (second motor neuron) is in an autonomic ganglion outside the CNS.

True or False? Autonomic ganglia are sights of synapse and information transmission from preganglionic to postganglionic neurons.

True. Autonomic postganglionic fibers release two neurotransitters -Norepinephrine (NE): secreted by sympathetic fibers -Acetylcholine (ACh): secreted by parasympathetic fibers.

True or False? The autonomic nervous system may cause activation or inhibition, depending on the division that is active and the target that is affected.

True. Autonomic postganglionic fibers release two neurotransmitters: NE (sympathetic) and ACh (parasympathetic). Depending on the type of receptors on the target organ, the effect may be excitatory or inhibitory.

True or False The sacral part of the parasympathetic division serves the pelvic organs and the distal half of the large intestine.

True. It arises from neurons located in the lateral gray matter of spinal cord segments S2-S4.

True or False Cranial nerves III (oculomotor), VII (facial), and IX (glossopharyngeal) supply the entire parasympathetic innervation of the head; however, only the preganglionic fibers lie within these three pairs of cranial nerves.

True. Many of the postganglionic fibers hitch a ride with branches of the trigeminal nerve (V), taking advantage of its wide distribution.