Autonomic Nervous System

Describe the 4 possible pathways of efferent neurons in the sympathetic nervous system.

1. Go out spinal nerve and synapse with chain ganglia 2. Go out spinal nerve, go through chain ganglia to the synapse at the collateral ganglia 3. Go out spinal nerve and enter the chain ganglia and move up to a higher chain and synapse 4. Go out spinal nerve and enter the chain ganglia and move down to a lower chain ganglia and synapse

The chain ganglia has a paired series of ___ ganglia located along the length of the vertebral column.

22

The neurotransmitter ___ is used in the parasympathetic division as an inhibitory neurotransmitter.

Acetylcholine

The sympathetic postganglionic fibers innervating the sweat glands of the skin and some blood vessels within the skeletal muscles and external genitalia are the neurotransmitter exception, releasing ___.

Acetylcholine

___ is released by all preganglionic axons of the ANS and all parasympathetic postganglionic axons at synapses with their effectors, therefore these fibers are cholinergic fibers

Acetylcholine

The neurotransmitter of the somatic system is ___, whereas the neurotransmitter(s) of the ANS are ___ and ___. Acetylcholine Acetylcholine and norepinephrine

Acetylcholine Acetylcholine and norepinephrine

Most glands are activated by parasympathetic fibers except ___ glands and ___ glands of the skin.

Adrenal glands and sweat glands

The ___, part of the endocrine system, is sometimes viewed as the "misplace" sympathetic ganglia because it arises from the same tissue. Its cells, located in postganglionic sympathetic neurons, secrete large amounts of norepinephrine and epinephrine into the blood. This hormone is carried to all parts of the body to reinforce the action of the sympathetic nerves. EX: adrenaline rush

Adrenal medulla

This adrenergic receptor is a vasoconstrictor, stimulatory.

Alpha receptors

What 2 kinds of adrenergic receptors does norepinephrine activate?

Alpha receptors and Beta receptors

This adrenergic receptor is a vasodilator, inhibitory.

Beta receptors

Name the 3 types of ganglia of ANS that is found outside the CNS. Note that the somatic system does not have any ganglia. Chain Collateral Terminal

Chain Collateral Terminal

In the sympathetic division of the ANS, preganglionic axons connect to either the ___ ganglia or the ___ ganglia.

Chain/Collateral

___ rapidly destroys acetylcholine after it is released, therefore parasympathetic effects are short-lived and brief compared to sympathetic.

Cholinesterase

Each postganglionic neuron may get input from many different preganglionic neurons. This process is called ___.

Convergence

Because of the origin in the cranial section and sacral area, the parasympathetic nerves are sometimes known as the ___. Craniosacral outflow

Craniosacral outflow

The parasympathetic system is located in the ___ region of the CNS because the preganglionic fibers spring from opposite ends of the CNS (brain and sacrum).

Craniosacral region

In the sympathetic nervous system, there are more postganglionic neurons than preganglionic neurons. Each preganglionic neuron synapses with 30 or more postganglionic neurons. This is a process called ___. As a result, the sympathetic effects tend to be widespread instead of precise, usually involving many organs simultaneously.

Divergence

The parasympathetic nervous system (does or does not) innervate blood vessels or sweat glands.

Does not

In what 3 ways does the ANS differ from the Somatic? Effectors Efferent pathways Neurotransmitter effects

Effectors Efferent pathways Neurotransmitter effects

The hypothalamus serves as the ___ and ___ brain, so therefore emotions influence ANS functioning and behavior.

Emotional and visceral

___ activates both alpha and beta receptors equally, however, ___ has a greater effect on the alpha receptors.

Epinephrine/norepinephrine

The ___ cranial nerve stimulates the nasal, lacrimal, and salivary glands.

Facial

The ___ cranial nerve activates parotid salivary glands.

Glossopharyngeal

The main function of the ANS is to maintain ___ and coordinate life processes essential for survival.

Homeostasis

The sympathetic and parasympathetic nervous systems counterbalance each other's activities in order to maintain ___. This is called dual innervation.

Homeostasis

The ANS has the same specific functions as the ___ because ___ is the main subcortical center of autonomic regulation. Hypothalamus/hypothalamus

Hypothalamus/hypothalamus

Name the 4 cranial nerves of the parasympathetic nervous system.

III oculomotor VII facial IX glossopharyngeal X vagus

The digestive system is mainly under the control of the parasympathetic nervous system. The parasympathetic stimulation ___ peristalsis and strong sympathetic stimulation ___ peristalsis.

Increases/Inhibits

The effect of Ach binding with muscarinic receptors is either ___ or ___, depednign on the target organ.

Inhibitory or Stimulatory

The Vagus nerve goes through ___ ganglia and ___ ganglia located within the target organ.

Intramural ganglia and terminal ganglia

The emotional response of the ___ lobe to danger and stress signals the hypothalamus to activate the sympathetic system to "fight or flight" status.

Limbic

Heart rate, blood pressure, and respiration are regulated by the ___ of the brain stem. Vomiting and respiration are regulated by the ___ of the brain stem. Medulla/Pons

Medulla/Pons

This cholinergic receptor is present in all effector cells stimulated by postganglionic parasympathetic neurons. It is also present where acetylcholine's neurotransmitter is sympathetic.

Muscarinic receptors

What 2 kinds of cholinergic receptors does acetylcholine activate?

Muscarinic receptors and nicotinic receptors

This cholinergic receptor is found on postganglionic neurons of the sympathetic and parasympathetic nervous systems. It contains the hormone producing cells of the adrenal medulla.

Nicotinic receptors

Postganglionic sympathetic neuron release ___ as a neurotransmitter, therefore they are adrenergic fibers.

Norepinephrine

The neurotransmitter ___ is used in the sympathetic division as an excitatory neurotransmitter.

Norepinephrine

The ___ cranial nerve innervates smooth muscle of the eye to cause the pupils to constrict and eye lens to bulge.

Oculomotor

The difference between the somatic and ANS in regards to their number of efferent pathways is that the somatic has ___ pathway(s) and the ANS has ___ pathway(s). One/Two

One/Two

Parasympathetic fibers have ___ pregangmpathetic axons and ___ postganglia axons, whereas sympathetic fibers have ___ preganglia axons and ___ postganglia axons.

Para = long pre Short post symp = short pre Long post

This division of the ANS conserves and restores energy. It decreases BP, decreases the rate of the heartbeat and stimulates the digestive system to process food. It allows the body to unwind as it performs maintenance activities and conserves body energy.

Parasympathetic

___ tone prevents unnecessary heart accelerations and also dictates the normal activity levels of the digestive and urinary tracts.

Parasympathetic tone

Unlike sympathetic, parasympathetic preganglionic neurons synapse with only a few postsynaptic neurons. Therefore, effects of parasympathetic system are more ___ and ___.

Precise and localized

The motor unit in the ANS is a 2 neuron chain, meaning there is a ___ which resides in the brain or spinal cord and it synapses with a ___ which is residing outside of the CNS. Its axon then extends to the effector organ.

Preganglionic neuron/postganglionic neuron

Some sympathetic postganglionic fibers re-enter the spinal nerves by way of the ___. These allow sympathetic output to reach all parts of the body without running through spinal nerves.

Rami communicantes

Ach and NE are not consistently either excitatory or inhibitory, it depends on the ___ they attach to.

Receptors

The ANS is functionally organized into ___ pathways. Sequence: The receptor within viscera triggers impulse, the afferent nerve sends impulse to CNS, integration occurs at various levels, decisions are made and sent along efferent nerves to the effector organ (smooth or cardiac muscle, diaphragm, or glands). Reflex

Reflex

Stimulation of both the alpha and beta receptors causes ___ of the intestine.

Relaxation

The ___ fibers from the 2nd, 3rd, and 4th sacral spinal nerves form pelvic nerves that innervate the distal portion of the large intestine, the urinary system, and the reproductive system including erectile tissues Sacral parasympathetic fibers

Sacral parasympathetic fibers

___ is the ground sate of our metabolic system, however, our digestive and urinary system are at their highest. This is because the parasympathetic system stimulates the kidney and digestive function by increasing the diameter of blood vessels and arteries.

Sleep

The ANS innervates ___ and ___ muscle, whereas the somatic stimulates ___ muscle. Smooth and cardiac muscle Skeletal muscle

Smooth and cardiac muscle Skeletal muscle

The effectors of the ANS are ___, ___, ___, and the ___. Smooth muscle Cardiac muscle Glands Diaphragm

Smooth muscle Cardiac muscle Glands Diaphragm

___ nerves are preganglionic neurons that do not end at the chain ganglia but instead pass on to ganglia located in the abdomen close to the aorta.

Splanchnic

The sympathetic pathway of the ANS is the ___ of metabolism, except for digestive and urinary systems, whereas the parasympathetic is the ___ of metabolism, except for the digestive and urinary systems.

Stimulator/restorative

The effect of Ach binding to Nicotinic receptor is always ___ and results in excitation of the neuron or effector cell.

Stimulatory

The "fight or flight" system is used to describe the ___ system. This means this system enables the body to cope rapidly with situations that threaten homeostasis. It functions to provide the optimal conditions for an appropriate response to some threat.

Sympathetic

The vascular system is almost entirely innervated by the ___ fibers.

Sympathetic

This division of the ANS mobilizes energy during times of stress. It increases BP, increases the speed rate and force of the heartbeat, increases blood sugar concentration and re-routes blood flow to skeletal muscles.

Sympathetic

Name the 2 divisions of the ANS. They serve the same visceral organs, but have opposite effects on them.

Sympathetic and parasympathetic

During times of stress, the ___ division can override ___ effects.

Sympathetic override parasympathetic

In the parasympathetic system, preganglionic axons extend from the CNS nearly all the way to the structures to be innervated. There they synapse with postganglionic neurons located in the ___ ganglia, which are very close to or within the target organs.

Terminal

What is the relation between the spleen and exercise?

The spleen cleans out debris of blood. When at rest, blood flows through the spleen. When exercising the spleen dilates and blood rushes out into the muscles.

Sympathetic fibers originate from the ___ region of the spinal cord.

Thoracolumbar region

(T or F) The same stimulus can affect both the somatic and autonomic systems. True

True

The ___ cranial nerve supplies 75% of all parasympathetic fibers.

Vagus

The ___ nerve innervates the heart, lung, liver, pancreas, esophagus, stomach, small intestine, and proximal portion of the large intestine.

Vagus

___ tone is the term for sympathetic fibers keeping the blood vessels in a continual state of partial constriction. These fibers deliver impulses more rapidly when faster blood delivery is needed, causing BP to rise and blood vessels to constrict.

Vasomotor (sympathetic) tone

Postganglionic neuron fibers travel with the other fibers of the spinal nerve, but eventually branch off forming a ___.

Visceral nerve