Chpt 11

BIOL 240 Exam 2

The efferent divisions of the peripheral nervous system are . . .

somatic motor division, autonomic division

___ division controls skeletal muscles through neuromuscular joints and is mostly voluntary

somatic

The efferent divisions of the peripheral nervous system are . . .

somatic motor division, autonomic division

___ division controls skeletal muscles through neuromuscular joints and is mostly voluntary

somatic

___ division controls cardiac and smooth muscles and glands in homeostasis, and is mostly involuntary

autonomic

the _ division controls antagonistic controls and agonists and antagonists in research and medicine

autonomic

The two branches of the autonomic system are the and

sympathetic, parasympathetic

the __ branch of the autonomic system promotes “fight or flight” mode

sympathetic

The branch promotes homeostasis and maintenance

parasympathetic

The parasympathetic maintains what is commonly known as the “____ and _” mode

rest, digest

much of homeostatic nervous regulation is __ and reflects a balance between opposing control systems

autonomic

__ activity prepares the body for short-term actions and responses

sympathetic

__ activity adjusts body physiology for long-term well-bring

parasympathetic

this part of the brain integrates much of our sensory information, and is also a major point of efferent control

hypothalamus

Coordination of homeostatic responses can occur in three ways

autonomic, endocrine, behavioral

The hypothalamus regulates . . .

water balance, temperature, hunger

The pons regulate . . .

respiration

The medulla regulates

respiration, cardiac, vomiting, swallowing

Autonomic control centers in the brain include . . .

hypothalamus, pons, medulla

The control of the __ division is unconscious, although we can become aware of its effects.

autonomic

Most internal organs are under control, and receive two separate nervous inputs with opposite effects

antagonistic

The _ nerve carries most of the parasympathetic information and contains about 75% if all parasympathetic fibers

vagus

The contains (sensory/efferent/both) nerves

both; sensory and efferent

Autonomic system efferent nerves are typically (mono/bi)-synaptic and make use of ganglia just outside of the CNS

bi

Bi-synaptic connections require _ synapses, and these differ between the sympathetic and parasympathetic systems

two

Neurons from both divisions use as the neurotransmitter at their ganglionic synapses

Acetylcholine (ACh)

neurons use Acetylcholine (ACh) at their target tissues, while neurons use Norepinephrine (NE).

parasympathetic, sympathetic

At their target tissues, autonomic neurons have many __ (swellings) which release neurotransmitter collectively at neuroeffector junctions

varicosities

Autonomic neuron NT release, function, and removal at neuroeffector junctions are of classic __ form

Chemical synapse

Much of the sympathetic activity is mediated by the release of epinephrine by the _ portion of the adrenal gland

medulla

The (cortex) region of the adrenal gland is glandular, while the _ (medulla) portion is a modified sympathetic ganglion

outer, inner

The _ is activated by spinal sympathetic input and releases adrenalin into the bloodstream

adrenal medulla

The adrenaline from the adrenals and norepinephrine from the sympathetic neurons act on (the same/different) target tissue receptors

the same

Pupil dilation, salivation, increased heart rate, and fat breakdown are all results of _ nervous activity

sympathetic

inhibited digestion, inhibited pancreas secretion, and inhibited urination are indicative of _ nervous activity

sympathetic

constricted pupils and bronchioles, slow heart rate, insulin release, urination, and digestion are indicative of _ nervous activity

parasympathetic

At parasympathetic target tissues, ACh acts upon receptors and triggers _ effects

muscarinic, metabotropic

The pathway provides voluntary control of skeletal muscles

Somatic

Motor neuron axons are mostly

myelinated

motor connections are , use Ach at nicotinic (ionotropic) receptors, and are

monosynaptic, excitatory

Neurons that innervate muscle fibers are termed , and the synapses they make are called

motor neurons, neuromuscular junctions (NMJs)

__ junctions are large, branched, and powerful

neuromuscular

neuromuscular junctions deliver a large amount of what neurotransmitter at once

Acetylcholine (ACh)

NMJ operation (in typical manner of chemical synapses- see other side)

Motor neuron action potential → \n Depolarization of the neuron terminal (at the NMJ) → \n Opening of voltage-gated Ca++ channels → \n Ca++ influx into neuron terminal → \n ACh vesicle cycling and ACh release into the synapse → \n ACh binds nicotinic ACh receptors on the muscle fiber → \n Na+ channels open, allowing Na+ influx into the muscle fiber → \n Muscle fiber depolarizes → \n Muscle fiber contracts