ap Flashcards

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