Autonomic Nervous System II Flashcards
What are the affects of the parasympathetics on the heart?
Decreases rate and strength of cardiac contraction
What are the affects of the parasympathetics on the eye?
Constricts pupil, accommodation - focusing close
What are the affects of the parasympathetics on the lungs?
Bronchoconstriction, increased bronchial secretion
What are the affects of the parasympathetics on the gastrointestinal tract?
Stimulates motility and secretion
What are the affects of the parasympathetics on the bladder?
Facilitates urination
What are the affects of the parasympathetics on the liver?
Promotes glycogen production, conservation and increased bile secretion
What are the affects of the parasympathetics on the reproductive organs?
Increase blood flow to erectile tissues
What two organs that were innervated by the sympathetic nervous system are not directly innervated by the parasympathetic nervous system?
Skin and adrenals
What is the basic plan of the parasympathetic nervous system?
Cranio-sacral origins, long Preganglionic neurons, short postganglionic neurons in or on target organs
The sacral origins of the PNS are at what spinal cord levels?
S2-S4
What are the 4 cranial nerves for parasympathetic outflow?
Oculomotor III, facial VII, glossopharyngeal IX, vagus X
Parasympathetics synapse in what ganglion before continuing to the eye?
Ciliary ganglion
The smooth muscle circular fibers of the eye ( sphincter papillae) contract to constrict the iris via what type of stimulation?
Parasympathetic CN III
The smooth muscle radial fibers ( dilator pupillae) contract to dilate the iris via what type of stimulation?
Sympathetic
Parasympathetics from the facial nerve VII traveling to the lacrimal gland, which induces tear production, synapse in what ganglia first?
Pterygopalatine ganglion
Parasympathetics from the facial nerve VII to the submandibular and sublingual salivary glands synapse in what ganglion before reaching their targets?
Submandibular ganglion
Parasympathetics traveling on the glossopharyngeal nerve to the parotid and glands in the posterior tongue synapse in what ganglion before reaching their targets?
Otic ganglion
Parasympathetics traveling in what nerve supply the thoracic and abdominal viscera?
Vagus
Parasympathetics to the head neck and most of trunk is supplied by what?
Cranial nerves
Parasympathetic innervation to the pelvic viscera and the reproductive organs is supplied by what?
Spinal cord level S2-S4
What PNS nerve carries Preganglionic neurons to the penis/clitoris, bladder, small intestine and large intestine from left colic flexors to rectum?
Pelvic splanchnic nerves
Intrinsic neuronal control is exemplified by what?
Peristalsis
Peristalsis is an example of what part of the ANS?
Enteric
What depends on neuronal activity, little influence on activity if a segment of the gut is surgically dennervated, reflex is preserved in gut removed from the body, all the neurons for the reflex are contained within the wall of the gut?
Peristalsis
A simple neuronal reflex consists of what?
Afferent sensory input, interneuron integration, efferent effector output
A sensory neuron flanked by an excitatory motor neuron and an inhibitory motor neuron connected by interneurons describes what?
A simple model for peristalsis reflex
What enteric nervous plexus is located between the longitudinal and smooth muscle of the GI tract?
Myenteric plexus
What enteric neuronal plexus is located closest to the lumen of the GI tract?
Submucous plexus
What plexus controls the longitudinal and circular muscles?
Myenteric plexus
What has 100 million neurons ( as many as in the spinal cord), distributed along the entire length of the GI tract, and organized into ganglia?
ENS
What is between the outer muscle layers and is mainly involved in motility?
Myenteric plexus
What is located in the submucosa between the mucosa and muscle and is mainly involved in control of secretion?
Submucosal plexus
What are the 2 main neuron shapes in the myenteric plexus?
Intrinsic sensory neurons and interneurons motorneurons
What has few dendrites on cell body, little input from other neurons, many output processes, and a single input from mucosa?
Intrinsic sensory neuron
What is the ratio of sensory neurons per mucosal villus?
1:1
What has many dendrites (inputs from other neurons), single output axon?
Interneurons motorneurons
Coordinated repeating and overlapping units is characteristic of what?
Peristalstic activity
What has 100 million neurons, does fine local control, can’t see big picture, reflexes triggered by local environment, neurons directly supply smooth muscle and glands?
Enteric nervous system
What has 100,000 neurons, controlling mechanism regulates the hard wired ENS to the overall needs of the individual, coordinates motility between different regions of the gut, neurons mainly supply the ENS, generally doesn’t micromanage motility and secretion, apart from reflexes such as vomiting and defacation?
SNS/PNS
