Autonomic Nervous System Flashcards
The CNS is comprised of:
pre-ganglionic ganglia
The PNS is responsible for:
Synapse of post ganglionic cells
The ANS functions without:
Conscious effort
During SNS activation, the adrenal medulla promotes secretion of:
Adrenaline and noradrenaline
During PSNS activation, the endocrine pancreas secretes:
Insulin and glucagon
During SNS activation, the endocrine pancreas promotes secretion of:
Insulin
Afferent neurons…
Are sensory, travel to the ventral horn
Efferent neurons…
Are motor, travel down to the dorsal horn
Define ganglia:
A bundle of nerves that sit within the ganglia and give-off post-ganglionic axons
The SNS has its motor neurons within the:
Thoracic and Lumbar regions
Within the SNS, ganglia are ____ to the spinal cord
Proximal
Within the SNS, pre-ganglionic axons are shorter than post-ganglionic axons. T/F
True
GI tract, urinary bladder and genitals activity decrease upon activation of the…
SNS
The PSNS has its motor neurons within the ____
Brain stem and sacrum
Within the PSNS, the ganglia are proximal to…
The organ innervated
Autonomic Ganglia:
Bridges the central motor neurons to effector organs
Post-ganglionic axons terminate at…
Varicosities embedded within smooth muscle
Single-unit smooth muscle cells are innervated by ___
Gap junctions
For contraction of multi-unit smooth muscle cells ____
Each cell must be individually innervated
i.e. within the eye
Autoinhibition:
Neurotransmitters act back on presynaptic membrane to inhibit further release
Activation of post-Synaptic adrenergic receptors (α1) by sympathetic nerve varicosities results in _____
Increased vasoconstriction.
What is the minimum number of neurons that neural signals must propagate through from a visceral sensory receptor to a visceral effector organ?
3
From a visceral sensory receptor, neural signals will travel through a sensory neuron (1) to a pre-ganglionic neuron (2) in the ventral horn of the spinal cord. This pre-ganglionic neuron will then synapse with a post-ganglionic neuron (3) in an autonomic ganglion. Finally, the post-ganglionic neuron will innervate a visceral effector organ.
Single-unit smooth muscle cells are able to contract simultaneously in a coordinated manner. Aside from the digestive system, where else in the body would single-unit smooth muscle cells exist?
Uterus and Bladder
Direct acting cholinergic agonists bind to ____
Muscarinic or nicotinic receptors –> release acetylcholine
Indirect acting reversible cholinergic agonists bind to ____
Acetylcholine
Which neurotransmitters is responsible for the activation of sweat glands under sympathetic activation?
Acetylcholine