Histology of Nervous Tissue Study Guide

Chapters 11-15

Central nervous system

CNS

Peripheral nervous system

PNS

Sensory afferent division

Made up of somatic sensory fibers and visceral sensory fibers

Somatic sensory fibers

Convey impulses from skin, skeletal muscle, and joints to the CNS

Visceral sensory fibers

Convey impulses from visceral organs to o CNS

Motor efferent division

Transmits impulses from CNS to effector organs

Motor efferent division

Made up of the somatic nervous System and autonomic nervous system

Somatic nervous system

Somatic motor nerve fibers; conducts impulses from CNS to skeletal muscle; voluntary nervous system

Autonomic nervous system

Visceral motor nerve fibers; Regulates smooth muscle, cardiac muscle, and glands; invuntary nervous system

Autonomic nervous system divisions

Sympathetic nervous system and Parasympathetic nervous system

Sympathetic nervous system

Mobilizes body systems during activity

Parasympathetic nervous system

Conserves energy and promotes house keeping functions during rest

Neuron body

Biosynthetic center of the neuron, synthesizes proteins, membranes, and other chemicals

Axon

Generates nerve impulses, carries on conversations, lacks rough ER

Dendrite

In motor neurons, input region of the neuron, convey messages towards the cell body

Amitotic

Neurons can not divide or reproduce after they are formend

100 years or more

Life span of a neuron

High metabolic rate

Neurons require continuous supply of oxygen and glucose

Astrocyte

Most abundant, supports, exchanges, guides, controls, and influences

Microglia

Touch and monitor neurons, migrate towars injured neurons, can transform to phagcytize microorganisms and neuronal debris

Epidymal

Line brain and spinal cavities, form permiable barriers between the CSF in cavitiea and fluid bathing CNS cells

Oligodendrocyte

Wrap around the CNS nerve fibers, and form myelin sheaths

Schwann

Surround peripheral nerve fibers and form myelin sheaths, and vital to regeneration in damaged nerve fibers

Satelite

Surround neuron cell bodies in PNS

Synapse

Junctions that mediate information transfer from one neuron to another, or a neuron to an effector cell

Synaptic cleft

Fluid filled space

Chemical impulse

Uses neurotransmitters to cross the synapse between cells

Eletrical impulse

Direct flow of ions through channels connecting the cytoplasm of adjacent cells

Acetylcholine

Released at neuromuscular junctions and plays a role in memory formation

Catecholamines

Dopamine, Norepinephrine, and Epinephrine neurotransmitters

Indolamines

Serotonin and Histamine

Melatonin

Influences the release of other neurotransmitters

Epineurium

The outermost layer of connective tissue in the nerves

Perineurium

Middle layer of connective tissue in the nerves

Endoneurium

Innermost connective tissue in the nerves

Nerve

Bundle of axons in the PNS

Tract

Bundle of axons in the CNS