Reading 2 Flashcards
______________ consists of the brain and the spinal cord, which occupy the cranium and the vertebral canal, respectively
Central Nervous system (CNS):
___________the part of the nervous system outside the CNS, consists mainly of the nerves that extend from the brain and spinal cord.
Peripheral Nervous system (PNS):
______________ carry signals to and from the brain
spinal nerves: carry signals to and from the spinal cord.
Cranial nerves:
____________ areas where neurons are clustered
Sensory or afferent division: signals are picked up by sensory receptors located throughout the body and carried by nerve fibers of the PNS into the CNS
Ganglia:
_____________ signals are carried away from the CNS by nerve fibers of the PNS to innervate the muscles and glands, causing these organs either to contract or to secrete (efferent means “carrying away”)
Motor or efferent division:
The four main divisions of the PNS
somatic sensory, visceral sensory, somatic motor, visceral motor
____________ (the sensory innervation of the outer tube: skin, body wall, and limbs);
somatic sensory
________________ (the sensory innervation of the viscera)
visceral sensory
________________r (the motor innervation of the outer tube, specifically skeletal muscles); and
somatic motor, or voluntary moto
______________the involuntary motor innervation of the inner tube, specifically smooth muscle, cardiac muscle, and glands, as well as some outer tube structures: arrector pili muscles, smooth muscle in the vessels, and sweat glands).
visceral motor:
______________ are the senses whose receptors are spread widely throughout the outer tube of the body\
General somatic senses:
_____________a sense that detects the amount of stretch in muscles, tendons, and joint capsules.
Proprioception:
______________are the somatic senses whose receptors are confined to relatively small areas rather than spread widely throughout the body
Special somatic sense:
_______________ include stretch, pain, and temperature, which can be felt widely in the digestive and urinary tracts, reproductive organs, and other viscera
General visceral senses:
____________ These senses, referred to also as the chemical senses, have their sensory receptors localized to the tongue and nasal cavity, respectively.
special visceral sense
_______________part of the PNS stimulates contraction of the skeletal muscles in the body. Because we have voluntary control over the contraction of our skeletal muscles,
Somatic motor:
__________________ part of the PNS regulates the contraction of smooth and cardiac muscle and secretion by the body’s many glands.
Visceral motor:
______________: which are the basic structural units of the nervous syste
Neuron:
These signals are transmitted along the plasma membrane, or neurilemma, in the form of nerve impulses, or _____________
action potentials
_____________: is also called a soma the largest part of the neuron. all consist of a single nucleus surrounded by cytoplasm
Cell Body:
_____________: substance is large clusters of rough endoplasmic reticulum and free ribosomes that stain darkly with basic dyes. These cellular organelles continually renew the membranes of the cell and the protein components of the cytosol
chromatophilic substance:
_____________: are bundles of intermediate filaments (neurofilaments) that run in a network between the chromatophilic substance.
Neurofibrals:
______________: clusters of cell bodies that lay on the cell body
Ganglia:
____________ function as receptive sites, providing an enlarged surface area for receiving signals from other neurons. By definition, dendrites conduct electrical signals toward the cell body.
Dendrites:
__________ The site at which neurons communicate
Synapse:
___________________ The neuron that conducts signals toward a synapse is called the
Presynaptic neuron:
_______________ the neuron that transmits signals away from the synapse is called
Postsynaptic neuron:
_____________ Most synapses occur between the terminal boutons of one neuron and the dendrites of another neuron
Axodendritic synapses:
____________These are membrane-bound sacs filled with neurotransmitters, the molecules that transmit signals across the synapse.
Synaptic vesicles:
_______________ are abundant in the terminal bouton because the secretion of neurotransmitters requires a great deal of energy.
Mitochondria
____________ are thin processes of uniform diameter throughout their length. By definition, axons are impulse generators and conductors that transmit nerve impulses away from their cell body.
Axons
____________ any long axon terminal
Nerve fiber:
___________ extend from the axon at more or less right angles.
axon collaterals,:
__________ undivided or has collaterals, it usually branches profusely at its end, called the terminal arborization.
Terminal arborization:
