Chaper 18: ANS Flashcards
Sensory nervous system
Detects stimuli and transmits information from receptor to the CNS
Somatic sensory nervous system
Sensory input that is consciously perceived from receptors (eye, skin, and ears)
Visceral sensory nervous system
Sensory input that is not consciously perceived from receptors of blood vessels and internal organs
Motor nervous system
Initiate and transmits information from the CNS to effectors
Somatic motor nervous system
Motor output that is consciously or voluntarily controlled; effector is a skeletal muscle
Autonomic motor system
Motor output that is not consciously or involuntarily controlled
- effectors are cardiac muscle, smooth muscle, and glands
Preganglionic axon (ANS)
- Myelinated
Postganglionic axon ( ANS)
Unmyelinated
Extends to the effector cells
Parasympathetic preganglonic axons
- long
- few branches
Parasympathetic postganglionic axons
- short
- in or close to effector
Sympathetic preganglionic axons
- short
- have many branches
- carried by white rami communicates
- terminates the sympathetic trunk
Sympathetic postganglionic axons
- long
- near the spinal cord
- carried by grey rami communicates
- extends within the spinal nerve to target organ
Sympathetic nervous system
Thoracolumbar division
- preganglonic neurons housed in the lateral horns
- more complex then parasympathetic
- brings body to homeostasis in conditions of “flight or fight”
- increase alertness in metabolic activities
Parasympathetic division
Crainosacral
Origin: preganglonic neurons located in the brain stem nuclei and S2-S4 segments of the spinal cord
Functions:
- brings body to homeostasis in the conditions of “rest and digest”
- conserves energy and replenishes nutrient stores
Sympathetic ganglia
Sites of synapses between the sympathetic preganglionic and postganglionic neurons
Sympathetic trunk ganglia
A vertical row in either side of the vertebral column
Prevertebral (collateral) ganglia
Lies anterior to the vertebral colon and close to the large abdominal arteries
Celiac ganglia
Adjacent to he origin of the celiac artery
Preganglonic axons: greater thoracic splanchnic nerves
Postganglionic axons: innervate the stomach, spleen, liver, gallbladder, proximal duodenum, and part of the pancreas
Superior mesenteric ganglia
Adjacent to the origin of the superior mesenteric artery
Preganglonic axons: compromise the lesser and least thoracic splanchnic nerves
Postganglionic axons: innervate distal duodenum, part of the pancreases, small intestine, proximal large intestine, kidneys, proximal part of the ureters
Superior Cervical ganglia
Postganglionic axons distribute to structure in the head and neck
Middle and inferior cervical ganglia
Postganglionic neurons extend to the thoracic viscera
Inferior mesenteric ganglia
Postganglionic axons innervate the distal colon, rectum, urinary bladder, distal utters, and most of the reproductive organs
Greater thoracic splanchnic nerves
T5-T9
Lesser thoracic splanchnic nerves
T10- T11
Least thoracic splanchnic nerves
T12
Lumbar splanchnic nerves
L1 and L2
Sacral splanchnic nerves
Sacral sympathetic ganglia
Parasympathetic division is also know as the
Craniosacral division
Cranial nerves associated with the parasympathetic division
- CN3: oculomotor
- CN7: facial
- CN9: glossopharyngeal
- CN10: Vagus
Terminal ganglia
Synapse with parasympathetic postganglionic neurons in the terminal ganglia
Ciliary ganglia
Parasympathetic preganglionic axons: pass with the oculomotor nerve to the ciliary ganglia
Postganglonic: project into the collars and iris muscles. Help with vision
Pterygopalagine
Parasympathetic
- pass through facial nerve
- postganglionic: lacrimal glands and glands of the nose, mouth and palate
Submandibular ganglia
Parasympathetic
- pass with through facial never
- postganglionic: submandibiular and sublingual salivary glands
Optic ganglia
Parasympathetic
- pass with glassopharyngeal nerve
- postganglionic: parotid glands
CN10
Vagus nerve
Innervates thoracic and abdominal organs
Thoracic organs
Increase mucous production, decreases airway diameter, decreases heart rate and force of contraction
Abdominal organs
Increases smooth muscle motility and secretory activity in the digestive tract
Pelvic splanchnic nerve
- large intestine, rectum. Reproductive organs, urinary bladder, and distal ureter
What releases Ach
All postganglionic parasympathetic axons
Cholinergic neurons
ACh real sing cells
Cholinergic neurons include
- all sympathetic and post sympathetic preganglionic neurons
- all parasympathetic postganglionic neurons
What are the two types of Cholinergic receptors which ACh binds to
- nicotinic receptors
- muscarinic receptors
What do adrenergic neurons release
Norepinephrine (noradrenaline)
What do adrenergic receptors bind to
Norepinephrine and epinephrine
What ANS neurons are adrenergic
Sympathetic postganglionic neurons
What do autonomic plexuses do?
- control pressure by adjusting heart rate
- ventricular contraction and blood vessel diameter
- adjust movement of digestion
Cardiac plexus sympathetic activity
Increase heart rate and blood pressure
Cardiac plexus parasympathetic activity
Decreases heart rate
Plums are plexus sympathizers activity
Bronchodilation
Pulmonary plexus parasympathetic activity
Bronchi constriction and increased secretion from the bronchial tree
Esophageal plexus parasympathetic axons control
Swallowing action
Abdominal aortic plexus consists of
Celiac plexus, superior and inferior mesenteric plexus
What does the hypogastric plexus supply to?
Supplies to the pelvic viscera - vagina, penis, bladder, and uterus
autonomic reflexes help to control
Homeostasis
What are autonomic reflexes
Consists of smooth and cardiac muscle contractions as well as gland secretion in response to a stimuli
