1. Nerves are bundles of Axons wrapped in layers of connective tissue. a. Nerve bundle of fascicles – b. Fascicles bundle of axons – 2. Connective Tissue Coverings a. Epineurium covers entire nerve – b. Perineurium surrounds each fascicle – Epineurium & Perineurium as passages for blood vessels c. Endoneurium surrounds each axon – Endoneurium contains capillaries provides gas/nutrient/waste exchange. – D. Classification of Peripheral Nerves 1. Definitions a. Sensory Nerves = Afferent b. Motor Nerves = Efferent c. Mixed Nerves = contain both Sensory and Motor Nerve Fibers d. Efferent = e. Somatic = Voluntary (skeletal muscles and cutaneous sensory) f. Visceral = Autonomic (visceral sensory, smooth muscles, cardiac muscles, and glands) g. General = distributed throughout the body: touch, temperature, pressure, h. Special = Localized in the head: vision, olfaction, hearing, balance, taste 2. Classifications of General Fibers a. General Somatic Efferent Fibers conduct motor impulses from brain or spinal – cord to skeletal muscles b. General Visceral Efferent Fibers conduct motor impulses from brain or spinal – cord to smooth muscles or glands associated with internal organs
1. Nerves are bundles of Axons wrapped in layers of connective tissue. a. Nerve – bundle of fascicles b. Fascicles – bundle of axons 2. Connective Tissue Coverings a. Epineurium – covers entire nerve b. Perineurium – surrounds each fascicle Epineurium & Perineurium as passages for blood vessels c. Endoneurium – surrounds each axon Endoneurium contains capillaries – provides gas/nutrient/waste exchange. D. Classification of Peripheral Nerves 1. Definitions a. Sensory Nerves = Afferent b. Motor Nerves = Efferent c. Mixed Nerves = contain both Sensory and Motor Nerve Fibers d. Efferent = e. Somatic = Voluntary (skeletal muscles and cutaneous sensory) f. Visceral = Autonomic (visceral sensory, smooth muscles, cardiac muscles, and glands) g. General = distributed throughout the body: touch, temperature, pressure, h. Special = Localized in the head: vision, olfaction, hearing, balance, taste 2. Classifications of General Fibers a. General Somatic Efferent Fibers – conduct motor impulses from brain or spinal cord to skeletal muscles b. General Visceral Efferent Fibers – conduct motor impulses from brain or spinal cord to smooth muscles or glands associated with internal organs
chapter-11-nervous-system-ii.docx