Chapter 13: Neural Tissue

what nervous system processes and integrates

CNS

what nervous system provides sensory info and carries motor commands to peripheral tissues

PNS

what are the 2 divisions of the PNS

afferent and efferent division

what are the 2 divisions of the efferent system

somatic and autonomic systems

what division of the PNS brings sensory info to CNS - Receptors

afferent

what division of the PNS carries motor commands

efferent

2 distinct cell types

neurons and neuroglia

neuroglia are…

supporting cells

responsible for the transfer and processing of info in the nevous system

neurons

what isolates the neurons

neuroglia - which are supporting cells

are there more neuroglia or neurons

neuroglia cells

what are the functions of neuroglia

provide framework for neural tissue, maintain intercellular tissue, act as phagocytes

what neuroglia are found in the CNS

ependymal, oligodendrocytes, astrocytes, microglia

what neuroglia are found in the PNS

satellite and schwann

what are the visceral sensory receptors

receptors from internal organs

what does it mena to myelinate mean

to cushion, protect

what neuroglia myelinates the axons and maintains framework

oligodendrocytes

what neuroglia are the largest and most numerous

astrocytes

what neurglia is the smallest and least amount

microglia

what neuroglia maintains the blood brain barrier, which regulates what goes in and out

astrocyte cells

what neuroglia removes wastes from cell by phagocytosis

microglia cells

what neuroglia lines the ventricles of brain and central canal of spinal cord, assists in producing CSF

ependymal

what neuroglia is myelin-forming cells that cover all peripheral axons, either myelinated or unmyelinated

schwann cells

what neuroglia encloses neuron cell bodies and regulates exchange of nutrients and waste products between neuron and extracellular fluid

satellite cells

juncton between neurons at neuroeffector junctions

synapse

chemical synapse which involves neurotransmitters

vesicular synapse

electrical synapse which invloves direct contacts between cells

nonvesicular synapse

neurons can be categorized into 3 functional groups

sensory, motor, interneurons

most sensory neurons are

pseudounipolar neurons

most motor neurons and interneurons are

multipolar neurons

sensory receptors: external enviornment

exteroceptors

sensory receptors: internal enviornment - position and movement of skeletal muscle

proprioceptors

sensory receptors: internal enviornment - internal systems, sensation of deep pressure/pain/ taste

interoceptors

ability of a plasmalemma to conduct electrical impulses

excitability

an electrical impulse or ? develops after the plasmalemma is stimulated to its threshold

action potential

action potential traveling along an axion

nerve impulse

rate of impulse conduction depends on 2 properties of the axon

presence of myelin sheath and diameter

what does myelin do

speeds impulse conduction

a coat of supporting-cell membranes around axons

myelin sheath

gaps in myelin sheath

nodes of ranvier

each axon is enclosed by

endoneurium

each fascicle of axons is wrapped by

perineurium

each whole nerve is surrounded by

epineurium