BIOL 031 Lecture Notes - Lecture 10: Postganglionic Nerve Fibers, Alpha Motor Neuron, Anterior Grey Column

• School: College of The Sequoias
• Department: Biology (BIOL)
• Course: BIOL 031
• Professor: carey

Document Summary

Distinguish between the afferent and efferent divisions of the peripheral nervous system. Single neuron travels from ventral horn of spinal cord to muscle (alpha motor neuron) Acetylcholine action receptors in muscle (nicotinic) always excitatory (depolarization. Autonomic branch (contains sensory, interneurons efferent neurons); involuntary smooth cardiac muscle, cardiac muscle, endocrine glands. 2 neuron pathway (1st preganglionic neuron, 2nd postganglionic neuron) 1st releases ach and bind to nicotinic. 2nd depends on the pathway (muscarinic or adrenergic receptors. 2nd (post) releasees norepi or epi onto adrenergic receptors. Adrenal medulla is modified postganglionic fiber and releases epi (80%) of the time or norepi (20%) into the blood as neuro hormones. Results: contraction of blood vessels, airways relax, glands release hormones, release of glucagon, inhibits release of insulin, increase of heart rate. Enteric ns (internal nervous system of the gut) Recognize that the efferent division is divided into somatic and autonomic systems, and that autonomic system is divided into the parasympathetic and sympathetic divisions.