Copyright © 2010 Pearson Education, Inc. Central nervous system (CNS)Peripheral nervous system (PNS) Motor (efferent) divisionSensory (afferent) division Somatic nervous system Autonomic nervous system (ANS) Sympathetic division Parasympathetic division Figure 13.1 Place of the PNS in the structural organization of the nervous system. Skeletal muscle Pg 484

Somatic Motor Pathway To Skeletal Muscle Primary Motor Cortex Upper Motor N. Lower Motor N. ACH Nicotinic Rec. Cross over at M.O. Axons in Corticospinal Tracts Anterior Horns Root? Branch?

Reflexes Involuntary Sensory in to spinal cord motor back out

Copyright © 2010 Pearson Education, Inc. The patellar (knee-jerk) reflex – a specific example of a stretch reflex Muscle spindle Quadriceps (extensors) Hamstrings (flexors) Patella Patellar ligament Spinal cord (L 2 – L 4 ) 3a 2 1 3b 1 Tapping the patellar ligament excites muscle spindles in the quadriceps muscle. 2 3a The motor neurons (red) send activating impulses to the quadriceps causing it to contract, extending the knee. Afferent impulses (blue) travel to the spinal cord, where synapses occur with motor neurons and interneurons. 3b The interneurons (green) make inhibitory synapses with ventral horn neurons (purple) that prevent the antagonist muscles (hamstrings) from resisting the contraction of the quadriceps. Excitatory synapse Inhibitory synapse – + Pg 516 Proprioceptor detects stretch 1 st order sensory Posture LMN Direct/Monosynaptic

Copyright © 2010 Pearson Education, Inc. + Excitatory synapse – Inhibitory synapse Quadriceps strongly contracts. Golgi tendon organs are activated. Afferent fibers synapse with interneurons in the spinal cord. Efferent impulses to muscle with stretched tendon are damped. Muscle relaxes, reducing tension. Efferent impulses to antagonist muscle cause it to contract. Interneurons Spinal cord 12 3a 3b Quadriceps (extensors) Golgi tendon organ Hamstrings (flexors) Pg 517 Indirect/Polysynaptic proprioceptor 1 st order sensory LMN

Copyright © 2010 Pearson Education, Inc. Figure 14.1 Place of the ANS in the structural organization of the nervous system. Central nervous system (CNS)Peripheral nervous system (PNS) Motor (efferent) divisionSensory (afferent) division Somatic nervous system Autonomic nervous system (ANS) Sympathetic division Parasympathetic division Pg 525 -Controls Cardiac and Smooth Muscle and Glands -Reflexes -Works with Endocrine Sys. Fight or FlightRest & Digest -Dual Innervation -Hypothalamus

Brain Stem or Lateral Horn Preganglionic N. B ACH Nicotinic Rec. Post- Ganglionic N. C Autonomic Nervous System Motor Pathway Reflexes faster or slower than Somatic?

Copyright © 2010 Pearson Education, Inc. Pterygopalatine ganglion Eye Lacrimal gland Nasal mucosa Ciliary ganglion Pterygopalatine ganglion Submandibular ganglion Submandibular and sublingual glands CN III CN VII CN IX CN X Otic ganglion Parotid gland Heart Lung Liver and gallbladder Stomach Pancreas Urinary bladder and ureters Small intestine Large intestine S2S2 Pelvic splanchnic nerves Genitalia (penis, clitoris, and vagina) Rectum Celiac plexus Inferior hypogastric plexus Cardiac and pulmonary plexuses S4S4 Preganglionic Postganglionic Cranial nerve Pg 528 Parasympathetic/Craniosacral Rest & Digest 3,7,9,10 Lat. Horn Terminal Ganglia (ACH Nicotinic Receptor) Post to Organ (ACH Muscarinic Receptor)

S 2 -S 4 Preganglionic axons exit out the Ventral Branch (Ramus)

LongShort Nicotinic Muscarinic 4.28a&b

Copyright © 2010 Pearson Education, Inc. Superior cervical ganglion Middle cervical ganglion Inferior cervical ganglion Sympathetic trunk (chain) ganglia Pons L2L2 T1T1 White rami communicantes Liver and gallbladder Stomach Spleen Kidney Adrenal medulla Small intestine Large intestine Genitalia (uterus, vagina, and penis) and urinary bladder Celiac ganglion Inferior mesenteric ganglion Lesser splanchnic nerve Greater splanchnic nerve Superior mesenteric ganglion Lumbar splanchnic nerves Eye Lacrimal gland Nasal mucosa Blood vessels; skin (arrector pili muscles and sweat glands) Salivary glands Heart Lung Rectum Cardiac and pulmonary plexuses Preganglionic Postganglionic Sacral splanchnic nerves Pg 532 Sympathetic/Thoracolumbar Fight or Flight Lat. Horns T1-L2 Gray Rami Autonomic Nerves NE to Alpha or Beta PreAortic G. Autonomic N. NE to Alpha or Beta

Copyright © 2010 Pearson Education, Inc. Spinal cord Dorsal root Ventral root Sympathetic Trunk (chain) ganglion Sympathetic trunk Rib Ventral ramus of spinal nerve Gray ramus communicans White ramus communicans Thoracic splanchnic nerves (a) Location of the sympathetic trunk Pg 530

T1-L2 ACH to Nic. Dorsal & Ventral Br. Muscarinic Alpha or Beta Aka Adrenaline & Noradrenaline -Bind to same receptors as NE -Enhances sympathetic effects -Lasts Longer Alpha Smooth (Exc.) Beta Smooth (Inh.) Cardiac (Exc.) 4.29a&b

Clicker Question: Which of the following statements are true? 1. The parasympathetic division shows less divergence than the sympathetic does so it’s effects are more localized and specific. 2. Skeletal muscle has nicotinic receptors on it to respond to stimulation. 3. The parasympathetic n.s. shuts down then the sympathetic n.s. is active, and vice versa. 4. Pelvic splanchnic nerves are preganglionic axons that branch out of dorsal branches (rami) of sacral spinal nerves. 5. Norepinephrine released by sympathetic postganglionic neurons binds to beta receptors on the smooth muscle of the stomach. A. 1,2,3,5B. 1,3,4C. 2,4,5D. 1,2,5