ANS Flashcards
what is the primary function of the ANS?
What controls it?
Its coordinated to what?
- homeostasis
- hypothalamus
- CNS, endocrine, immune systems
T/F: the ANS is a sensory system
F: motor
How is the final common pathway of ANS different than the somatic motor system?
- 2 neuron chain LMN organization
- preganglionic neuron (CNS) and post ganglionic neuron (ANS)
what are the target tissues of the postganglionic (ANS) neurons?
smooth muscle
cardiac muscle
glands
what are the 2 major divisions of ANS?
SNS ________
PSNS _______
- thoracolumbar
- craniosacral
SNS preganglionic cell bodies?
Location ?
-located in interomedial cell column (lateral horn) of spinal cord levels –
T1-L2 (thoracolumbar)
SNS preganglionic cell bodies?
Direction of short myelinated axon?
sympathetic chain ganglion
SNS preganglionic cell bodies?
Neurotransmitter?
Acetylcholine
SNS postganglionic cell bodies?
- location?
-ventral roots of spinal nerves T1-L2
SNS postganglionic cell bodies?
Direction?
target organs
SNS postganglionic cell bodies?
Neurotransmitter?
norepinephrine
SNS postganglionic cell bodies?
Innervation?
adrenal medulla
-releases norepinephrine hormonally
PSNS preganglionic cell bodies
location?
Interomedial cell column (horn) of S2-S4
cranio sacral
PSNS preganglionic cell bodies
direction?
peripheral ganglion
PSNS preganglionic cell bodies
Neurotransmitter?
Ach
PSNS postganglionic cell bodies
location?
ganglion located near target organ
PSNS postganglionic cell bodies
Neurotransmitter?
Ach
Divergence:
preganglionic axon can synapse on more than one postganglionic cell body
Convergence
several preganglionic axons can synapse on one single postganglionic cell body
What system controls the tone of smooth muscles?
What changes flow?
SNS
-pre capillary sphincters
What parts of the eye are controlled by SNS vs. PNS?
Loss of each results in what?
constrictor pupillae - PSNS
dilator pupillae - SNS
Loss of PSNS - dilation of pupil to unopposed SNS tone
Loss of SNS - Horners syndrome -
T/F: cord lesions that leave sacral levels intact result in loss of micturition (urination) reflex
F
Bladder control?
SNS- relax detrusor to fill bladder
PSNS- contract detrusor to empty
What has a powerful influence on the ANS by way of influencing hypothalamus?
Limbic system
_____ serves as the UMN of the ANS. Descending info projects to both SNS and PNS via _________ pathways
- hypothalamus
- RF
What emotions does the hypothalamus help you express in terms of motor activity?
Where do such emotions arise?
- rage, fear, aversion
- limbic system
what occurs with rage?
What structures get activated?
-defensive behaviors
-Medial hypothalamus and medial amygdala
-
What does each structure do in terms of rage?
- Medial hypo- motor manifestation of rage
- medial amygdala - emotional component of rage
rage behaviors elicited by innocuous (not normally disturbing) stimuli is due to what?
tumors;
Damage to temporal limbic structures, amygdala, or hippocampus
