click below
click below
Normal Size Small Size show me how
Nervous System (Gen)
General nervous system info
Question | Answer |
---|---|
Two main divsions of nervous system | central, peripheral |
CNS (Central Nervous System) | consists of the brain and spinal cord |
Peripheral nervous system | nerves tissues in the periphery or outer region of the nervous system |
Somatic Nervous Systen | motor neurons that control voluntary actions of skeletal muscles |
Divisions of SNS | somatic sensory division (afferent), somatic motor division (efferent) |
Divisions of ANS | visceral sensory division (afferent), sympathetic division (efferent), parasympathetic division (efferent) |
afferent division | incoming sensory pathways (carry toward) |
efferent division | all outgoing motor pathways (carry away) |
neurons | nerve cell including its processes (axons and dendrites); excitable cells that conduct impulses that make possible all nervous system functions "wiring" of nervous system |
Glia / neuroglia | nonexcitable supporting cells of nervous tissue |
Types of glia cells | astrocytes, microglia, ependymal cells, ogliodendrocytes, schwann cells, satelite cells |
astrocytes | star shaped; help form blood brain barrier, recycle neurotransmitters |
microglia | macrophages that engulf microorganisms and dead neuro tissue/cellular debris |
ependymal cells | line cavities of brain and spinal cord; form thin sheets that line the fluid filled cavities in the brain and spinal cord |
ogliodendrocytes | act as insulation, help form myelin sheaths |
schwann cells | found only in the peripheral nervous system; wrap around axons to from myelin sheath |
functional classification of neurons | afferent (sensory), efferent (motor), interneurons (association) |
reflex arc | impulse conduction route to and from the CNS; smallest portion of the nervous system that can receive stimulus and generate a response |
saltatory conduction | process in which a nerve impulse travels along a myelinated fiber by jumping from one node of Ranvier to the next |
classification of neurotransmitters | acetylcholine, amines, amino acids, other small molecules |