1. Intro Flashcards
nervous system: overall functions
- enables body to react to continuous changes in internal and external environments
- controls and integrates body’s activities
ways to organize the nervous system
- structurally
- CNS
- PNS
- functionally
- somatic nervous system
- autonomic nervous system
lobes of the cerebrum, and function
- frontal
- higher mental processes (thinking, decision-making, and planning)
- parietal
- processes sensory information
- occipital
- processes visual information
- temporal
- processes auditory information
CNS is protected by:
- skull
- vertebrae & meninges
spinal nerve (PNS)
emerges from between 2 adjacent vertebrae
spinal cord (CNS) has 2 paths
- ascending information, and
- descending information
peripheral nervous system (structural organization)
- consists of nerve fibers and cell bodies outside the CNS that conduct impulses to/away from CNS
- organizes into nerves which connect the CNS w/ peripheral structures
2 types of tissue components (cell types & function)
- neurons: nerve cells specialized for rapid communication
- neuroglia: support cells; there are 5 neuroglia per neuron
structure of a neuron
- dendrites: stim. by environmental changes or the activities of other cells
- cell body: contains nucleus, mitochondria, ribosomes, and other organelles, and incl.
- axon: conducts nerve impulse (AP) toward synaptic terminals
- terminal boutons: affects another neuron or effector organ (muscle or gland)
types of synapses
- neuron-neuron
- neuromuscular
- neuroglandular
nerve fiber: define
- axon and its coverings
- Nerve may be bundled together w/ lots of individual nerve fibers (wrapped in endoneurium) then bundles wrapped in perineurium –> then altogether wrapped in epineurium
two types of info conveyed by spinal nerves? pathway?
- motor info –> muscle or gland
- sensory info –> from receptor organ
which nerve root carries sensory information
A) dorsal root, bc it has dorsal root ganglion w/ sensory neuron cell bodies
good example of a dermatome
herpes zoster virus: will reside in the dorsal root ganglia after chicken pox –> can become reactivated and be responsible for Shingles (and follows T5 dermatome)
• Dermatome - unilateral distribution on patch of skin attributed to a single vertebral level
somatic nervous system: define, function
- soma means “body”
- composed of SOMATIC parts of CNS & PNS
- provides sensory and motor inn to all parts of body, except:
- viscera (organs) in body cavities
- smooth muscle
- glands
somatic sensory system: define
- transmits sensations of touch, pain, temp, & position from sensory receptors
- impusles enter spinal cord via dorsal root
somatic motor system: define
- innervates only skeletal muscle
- stimulates voluntary and reflexive movement by causing the muscle to contract
- impulses exit spinal cord via ventral root
autonomic nervous system: define
- motor fibers stimulate
- smooth (involuntary) muscle
- modified cardiac muscle
- glandular (secretory) cells
- 2 neuron system
- presynaptic - cell body in CNS
- postsynaptic - cell body outside CNS (PNS)
2 divisions of the autonomic nervous system
- sympathetic: “fight or flight”
- fxn: blood vessel regulation
- parasympathetic: “nap & crap”
- fxn: maintain homeostasis
sympathetic division of ANS
(location, structure)
- thoracolumbar origin
- 2-neuron system:
- presynaptic: cell bodies in gray matter of spinal cord
- post synaptic: cells bodies in sympathetic chain ganglia
which autonomic nervous system division originates at:
thoracolumbar?
sympathetic division
parasympathetic division:
location and structure
- craniosacral origin
- 2-neuron system
- presynaptic
- cell bodies in brainstem or sacral spinal cord
- postsynaptic
- cell bodies located at effector organ
- presynaptic
which autonomic system division has:
craniosacral origin
parasympathetic division
