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| 2728768714 | Autonomic Nervous System | The ANS consists of motor neurons that: Innervate smooth and cardiac muscle and glands Make adjustments to ensure optimal support for body activities Operate via subconscious control Have viscera as most of their effectors | 0 | |
| 2728770444 | Effectors | The effectors of the (somatic)SNS are skeletal muscles The effectors of the ANS are cardiac muscle, smooth muscle, and glands | 1 | |
| 2728771485 | Efferent Pathways | Heavily myelinated axons of the somatic motor neurons extend from the CNS to the effector Axons of the ANS are a two-neuron chain The preganglionic (first) neuron has a lightly myelinated axon The ganglionic (second) neuron extends to an effector organ | 2 | |
| 2728771852 | Neurotransmitter effects | All somatic motor neurons release Acetylcholine (ACh), which has an excitatory effect In the ANS: Preganglionic fibers release ACh Postganglionic fibers release norepinephrine or ACh and the effect is either stimulatory or inhibitory ANS effect on the target organ is dependent upon the neurotransmitter released and the receptor type of the effector | 3 | |
| 2728772839 | Divisions of ANS | ANS divisions: sympathetic and parasympathetic The sympathetic mobilizes the body during extreme situations The parasympathetic performs maintenance activities and conserves body energy The two divisions counterbalance each other | 4 | |
| 2728773417 | Paraymphathetic division | Concerned with keeping body energy use low Involves the D activities - digestion, defecation, and diuresis Its activity is illustrated in a person who relaxes after a meal Blood pressure, heart rate, and respiratory rates are low Gastrointestinal tract activity is high The skin is warm and the pupils are constricted | 5 | |
| 2728774040 | Sympathetic roles | The sympathetic division is the "fight-or-flight" system Involves E activities - exercise, excitement, emergency, and embarrassment Promotes adjustments during exercise - blood flow to organs is reduced, flow to muscles is increased Its activity is illustrated by a person who is threatened Heart rate increases, and breathing is rapid and deep The skin is cold and sweaty, and the pupils dilate | 6 | |
| 2728775255 | Anatomy of ANS | sympathetic: Thoracolumbar region of the spinal cord parasympathetic: Cranialsacral Brain and sacral spinal cord | 7 | |
| 2728777005 | Sympathetic Outflow | Arises from spinal cord segments T1 through L2 Sympathetic neurons produce the lateral horns of the spinal cord Preganglionic fibers pass through the white rami communicantes and synapse in the chain (paravertebral) ganglia Fibers from T5-L2 form splanchnic nerves and synapse with collateral ganglia Postganglionic fibers innervate the numerous organs of the body | 8 | |
| 2728777371 | Sympathetic trunk and pathways | The paravertebral ganglia form part of the sympathetic trunk or chain Typically there are 23 ganglia - 3 cervical, 11 thoracic, 4 lumbar, 4 sacral, and 1 coccygeal | 9 | |
| 2728778395 | Sympathetic trunk and pathways | A preganglionic fiber follows one of three pathways upon entering the paravertebral ganglia Synapse with the ganglionic neuron within the same ganglion Ascend or descend the sympathetic chain to synapse in another chain ganglion Pass through the chain ganglion and emerge without synapsing | 10 | |
| 2728778769 | Pathways with synapses in chain ganglia | Postganglionic axons enter the ventral rami via the gray rami communicantes These fibers innervate sweat glands and arrector pili muscles Rami communicantes are associated only with the sympathetic division | 11 | |
| 2728782701 | Pathways to the head | Preganglionic fibers emerge from T1-T4 and synapse in the superior cervical ganglion These fibers: Serve the skin and blood vessels of the head Stimulate dilator muscles of the iris Inhibit nasal and salivary glands | 12 |
