Test #1: Ch. 13 Flashcards
Divisions of the nervous system
Central nervous system (CNS) & Peripheral nervous system (PNS)
The peripheral nervous system has two major subdivisions
1) somatic motor system
2) autonomic nervous system
The autonomic nervous system is further subdivided into
1) parasympathetic nervous system
2) sympathetic nervous system
Which system controls voluntary movement of muscles?
somatic motor system
Which system controls involuntary processes?
autonomic nervous system
The autonomic nervous system has 3 principle functions
1) regulation of the heart
2) regulation of secretory glands
3) regulation of smooth muscles
Functions of the parasympathic nervous system
1) slow heart rate
2) increase gastric secretion
3) emptying bladder
4) emptying bowel
5) focusing the eye for near vision
6) constricting the pupil
7) contracting bronchial smooth muscle
Functions of the sympathetic nervous system
1) regulating the cardiovascular system
2) regulating body temp
3) implementing the acute stress response–“fight or flight”
Parasympathetic nerves ______ heart rate
slow
Sympathetic nerves _______ heart rate
increase
What is the feedback regulation?
a process that allows a system to adjust itself by responding to incoming information.
What is a baroreceptor reflex?
the most important feedback loop of the autonomic nervous system is one that helps regulate blood pressure. This reflex is important to us because it frequently opposes our attempts to modify bp with drugs.
What is autonomic tone?
steady, day to day influence exerted by the autonomic nervous system on a particular organ or organ system.
What system provides the predominant tone for most organs?
parasympathetic nervous system
What system provides the predominant tone for the vascular system?
sympathetic nervous system
The anatomy of the parasympathetic nervous system offers two general sites at which drugs act:
1) the snyapses between pre-gnaglionic neurons and post ganglionic neurons
2) the junctions between post-ganglionic neurons and their effector organs.
The adrenal medulla influences the body by releasing _______ into the bloodstream.
epinephrine.
The peripheral nervous system employs 3 neurotransmitters:
acetylcholine, NE, & Epi
_______ is the major transmitter released by the adrenal medulla
epinephrine.
_______ is the transmitter release by practically all postganglionic neurons of the sympathetic nervous system.
norepinephrine
There are 2 basic categories of receptors associated with the peripheral nervous system:
1) cholinergic receptors
2) adrenergic receptors
cholinergic receptors
receptors that mediate responses to acetylcholine
adrenergic receptors
receptors that mediate responses to epinephrine (adrenaline) and norepinephrine
3 major subypes of cholinergic receptors
1) nicotinicN
2) nicotinicM
3) muscarinic
4 major subtypes of adrenergic receptors
1) alpha1
2) alpha2
3) beta1
4) beta2
KNOW TABLE 13-2 (p110)
Functions of Peripheral Cholinergic Receptor Subtypes
KNOW TABLE 13-2 (p111)
Functions of Peripheral Adrenergic Receptor Subtypes
activation of nicotinicN (neuronal)
these receptors promote ganglionic transmission and release of epi from the adrenal medulla
activation of nicotinicM (muscle)
these receptors cause contraction of skeletal muscle
activation of muscarinic
these receptors increase glandular secretions, contraction of smooth mm, slowing of HR, contraction of sphincter mm of iris, contraction of ciliary mm of eye, dilation of blood vessels, and voiding of urinary bladder
where are alpha1 receptors located?
eyes, blood vessels, male sex organs, prostatic capsule, and bladder
where are alpha2 receptors located?
nerve terminals and not on the organs innervated by the autonomic nervous system.
where are beta1 receptors located?
heart and kidney
where are beta2 receptors located?
lungs, uterus, arterioles of heart, and skeletal muscles
where are dopamine receptors located?
vasculature of the kidney
epinephrine can activate ___________________
all alpha and beta receptors, but not dopamine receptors.
norepinephrine can activate ___________________
alpha1, alpha2, beta1, but not beta2
dopamine can activate _____________________
alpha1, beta1, dopamine
activation of beta2 receptors will (4)
1) dilate blood vessels in the heart, lungs, and skeletal mm
2) dilate the bronchi thereby increasing oxygenation
3) increase glycogenolysis there by increasing available energy
4) relax uterine smooth mm
the baroreceptor reflex helps regulate __________
blood pressure
Pathways from the spinal cord to organs under sympathetic & parasympathetic control consist of two neurons:
1) preganglionic neuron
2) postganglionic neuron
