Crash Course # 14 - Flashcards
Which division of the nervous system responds to stress?
Sympathetic
The sympathetic ns blasts all of your ______ to your brain, heart, and muscles to deal with the stressor/threat at hand.
resources
Physiological responses to non-immediate stresses like paying a bill on time are largely the same as when you are fighting for ______.
survival.
In the autonomic NS, there are ___neurons involved. The 1st is the preganglionic neuron which synapses in a ganglion, and the 2nd is the ____ neuron which synapses again when it reaches the effector organ.
2, postganglionic
The stress response involves two kinds of chemicals:
a. ______- made and released from neurons.
b. ______- secreted from glands, flow through the bloodstream.
Neurotransmitters
Hormones
The very same chemical substance can have _____effects depending on where it is received in your body.
opposite
Smoke alarm goes off - you smell smoke - realize you need to move fast - your brain sends action potentials down your spinal cord - preganglionic axons carry the signal to ganglia. Inside a ganglion, the end bulbs release NT ______- (full name) called ACh - ______ (full name)
neurotransmitters
Acetylcholine
The terminal end bulbs of the postganglionic fibers release into the ________ synaptic cleft. Norepinephrine crosses the final synapse and causes a response in the effector.
norepinephrine
Preganglionic fiber | Short - bc sympathetic trunk (aka sympathetic chain ganglion) is nearby | Releases..______.
ACH
Postganglionic fiber |Length _____- travels all the way to effector | Releases_______
Long
Norepinephrine
Exception to the two-neuron rule:
Adrenal Glands.
These, like all preganglionic fibers, release ACH which triggers the adrenal medulla (center of the adrenal gland) to release a flood of norepinephrine and epinephrine - hormones that rush through your ____ towards your organs (effectors).
bloodstream
How can norepinephrine, released in Hank’s fire example, elicit opposite responses (increased blood flow to large muscles and decreased blood flow to digestive tract) depending on the specific type of _____________
Receptors
Norepinephrine affects smooth muscle. _______ muscle is unstriated, involuntary muscle found in hollow organs like the stomach, intestine, bladder, and blood vessels.
Smooth
he lumen size can also be decreased when the smooth muscle wrapped around it constricts (_______) thus reducing blood flow.
vasoconstriction
How does the size of the lumen in blood vessels change during vasodilation and vasoconstriction?
Vasodilation increases lumen size, promoting more blood flow, while vasoconstriction decreases lumen size, restricting blood flow.
Alpha | Contract - vasoconstriction, reduced blood flow through vessel (less oxygen) | Blood vessels in the _________
digestive tract
Beta | Relax - ________ , increase blood flow through blood vessel (more oxygen) | Blood vessels serving skeletal muscles
dilation
