ANS 1 Flashcards
CNS is the
brain and spinal cord
PNS is comprised of what two systems
Afferent and Efferent
The Afferent Sensory system is made up of
general and special senses
The Efferent motor system is
divided into the somatic and autonomic nervous system
The somatic system controls
Skeletal muscles
The Autonomic nervous system control
Smooth muscles, cardiac muscles, glands
The autonomic nervous system operates with conscious or unconscious control?
Unconscious
The ANS is responsible for coordinating processes that
maintain homeostasis
The ANS is divded into
Sympathetic and Parasympathetic divisions
The sympathetic division of the ANS
uses energy
dominant in conditions of physical or emotional stress
“fight or flight”
The parasympathetic division of the ANS
Conserves and restores energy
Dominant control during rest
“Rest and digest”
What are the effectors with dual innervation?
Heart
Pupils
Digestive tract
Bronchioles
Define dual innervation
An effector innervated with both sympathetic and parasympathetic stimulation
How do sympathetic and parasympathetic systems effect the heart
Sympathetic increases heart rate
Parasympathetic decreases heart rate
How do sympathetic and parasympathetic systems effect the pupils
Sympathetic dilates pupils
Parasympathetic constricts pupils
How do sympathetic and parasympathetic systems effect the digestive tract
Sympathetic decreases motility and secretions
Parasympathetic increases motility and secretions
How do sympathetic and parasympathetic systems effect the bronchioles?
Sympathetic dilates airways
Parasympathetic constricts airways
What effectors have sympathetic input only?
Sweat glands
Arrector Pili muscles
Blood vessels of skin, skeletal muscle, heart, lungs, brain, digestive viscera, and kidney
How does sympathetic activity effect sweat glands?
Increased secretion
How does sympathetic activity effect arrector pili muscles?
contraction
How does sympathetic activity effect blood vessels of skin skeletal muscle, heart, lungs, and brain?
Dilation
How does sympathetic activity effect blood vessels of digestive viscera and kidney?
Constriction
What effectors have only parasympathetic input?
Lacrimal glands
How does parasympathetic activity effect lacrimal glands?
Increased secretion
The efferent pathway is a ____ neuron pathway
Two
Describe cell communication in the efferent pathway
Motor neurons in CNS send preganglionic axons to synapse on autonomic ganglia in PNS. These ganglia send postganglionic axons to synapse on effector
Describe the structure of the Sympathetic pathway
Thoraco-lumbar division
Preganglionic cell body in T1-T2
Ganglion closer to CNS
Have: sympathetic chain ganglia, collateral ganglia, adrenal medulla
Describe the structure of the parasympathetic pathway
Cranio-sacral division Preganglionic axon longer Ganglion near or in effector organ Postganglionic axon short Preganglionic cell body in Cranial nerves and S2, S3, and S4
Define sympathetic chain ganglia
2 chains of ganglia, one on each side of vertebral column, innervate head, body wall, limbs, and viscera of thoracic cavity
Define collateral ganglia
Close to abdominal argeries
Pass through chain ganglia and form splanchnic nerves
Innervated abdominal and pelvic viscera
Sympathetic activation of the collateral ganglia
decreases blood flow and releases stored energy molecules
Define adrenal medulla
Central portion of adrenal gland
Postganglionic cells are modified neurons that secrete into blood rather than onto effectors
The parasympathetic division has preganglionic neurons in
the brainstem and sacral segments of spinal cord
