A/P chapter 16

• 1. Somatic Nervous System: Composed of nerve fibers that send impulses from the central nervous system to skeletal muscle.
• 2. Number of Synapses if ONE- between the somatic motor neuron and the skeletal muscle.
• 3. The Neurotransmitter- Is ACETYLCHOLINE

• 1. Autonomic Nervous System- Nervous system composed of nerve fibers that send impulses fromt he central nervous system to smooth muscle, cardiac muscle, and glands
• 2. Locations of the two synapses are: first in the Autonomic ganglion (preganglionic) to the target issue (postganglionic)
• 3. The neurotransmitters made: ACETYLCHOLINE (preganglionic), and ACETYLCHOLINE or NOREPINEPHRINE (postganglionic)

• 1. In the Lateral horns of the spinal cord (T1-L2)
• 2. THORACOLUMBAR DIVISION

Preganglionic axons from a spinal nerve pass through a white ramus communicans into a sympathetic chain ganglion (aka paravertebral ganglia). Some axons synapse with a postganglionic neuron at the level of entry; others ascend or descend to other levles before synapsing. Each postganglionic axon exits the sympathetic chain through a gray ramus communicans and enters a spinal nerve.

Paravertebral ganglia.

Connects the Sympathetic chain ganglia (paravertebral ganglia) to the postganglionic neuron.

• 1. Spinal Nerves
• 2. Sympathetic nerves
• 3. Splanchnic nerves
• 4. Adrenal gland

Because it goes directly to specialized cells in the adrenal medulla.

• 1. They are in the brainstem and in sacral nerves 2-4
• 2. Craniosacral division

• 1. Cranial Nerves: III (Occulomotor), VII (Facial), IX (Glossophayneal), X (vagus)
• 2. Pelvic Splanchnic Nerves
• 3. Terminal Ganglia

• 1. Sympathetic- SHORT preganglionic, LONG postganglionic
• 2. Parasympathetic- LONG preganglionic, SHORT postganglionic

• 1. Walls of the digestive organs (like the stomach)
• 2. ??? I don't know what this means....

• 1. Spinal Nerves
• 2. Head and neck nerve plexuses
• 3. Thoracic Nerve plexus
• 4. Abdominopelvic nerve plexuses

• 1. Cardiac Plexus (heart)
• 2. Pulmonary Plexus (lung)

• 1. Celiac plexus-(diaphragm, stomach, spleen, liver, gallbladder, adrenal glands, kidneys, testes, and ovaries.)
• 2. Superior mesenteric plexus- (pancreas, small intestines, ascending colon, and transverse colon)
• 3. Inferior mesenteric plexes- (Transverse colon to the rectum)
• 4. Superior and inferior hypogastric plexuses- (Descending colon to the rectum, urinary bladder, and reproductive organs)

• 1. Oculomotor (III), Occasionally
• 2. Facial (VII), Feels
• 3. Glossopharyngeal (IX) Glossy

• 1. Thoracic Organ- Cardiac, pulmonary, and esophageal plexuses
• 2. Abdominal Organ- Stomach, celiac, and superior mesenteric plexuses.

Abdominoplevic organs

• 1. All preganglionic neurons of the sympathetic and parasympathetic divisions and all postganglionic neurons of the parasympathetic division.
• 2. Cholinergic Neuron

• 1. Almost all postganglionic neurons of the sympathetic division are adrenergic.
• 2. Adrenergic neuron

• 1. Nicotinic- are found in the postganglionic neurons and the membranes os skeletal muscle cells.
• 2. Muscarinic- are found in efferctor organs.

In effector organs.

• 1. nicotinic-Produce an excitatory response to acetylcholine
• 2. alpha and beta-Produce an excitatory or inhibitory response to norepinephrine.

• 1. Because they respond to acetylcholine
• 2. Because they respond to norepinephrine.

Hypothalamus and higher brain centers (??)

Central.

• 1. They Sympathetic action inhibits (prevent)
• 2. The Parasympathetic action stimulates (increased action)

Thoughts and emotions can influcence ANS functions thourgh the hypothalamus

Anutonomic Nervous System integrating center that interacts with the cerebrum, limbic system, brainstem, and spinal cord; also regulates body temperature.

Autonomic Nervous System relfex centers for controlling pupil size, accommodation, tear production, salivation, coughing, swallowing, digestive activities, heart rate and force of contraction, blood vessel diameter, and respiration.

Autonomic Nervous System centers for regulating defecation, urination, penile and clitoral erection, and ejaculation.

• 1. Both divisions of the Autonomic nerve system produce stimulatory and inhibitory effects.
• 2. Most organs are innervated by both divisions of the Autonomic Nerve System. There is not an equal distribution of the two divisions.
• 3. When an organ is innervated by both divisions of the autonomic nervous system, opposite effects are observed. (digestive, urinary)
• 4. Either the sympathetic or parasympathetic division alone or both working together can coordinate the activities of different structures.
• 5. The sympathetic division has a more general effect than the parasympathetic division. (the sympathetic division diverges more: there are more postganglionic (long) neuron connections)
• 6. Sympathetic activity generally prepares the body for physical activity.
• 7. Parasympathetic activity is more important for vegetative functions (digestion activities)

• SLUDD stand for parasympathetic activities:
• 1. Salivation
• 2. Lacrimation (tears)
• 3. Urination
• 4. Digestion
• 5. Defecation

Fight or Flight

Vegatative State

• 1. Increase heart rate
• 2. Blood vessel dilation in skeletal and cardiac muscles.
• 3. Dilation of air passageways and dilation of the pupil of the eye
• 4. Energy source availability is increased as glycogen is changed to glucose and fat cells break down triglycerides.
• 5. Muscles generate heat and body temperature increases.
• 6. Sweat gland activity increases.
• 7. Decrease in nonessential organ activities (digestion)