Nervouse System Flashcards
Sympathetic division. S/S
Fight or flight (prepares body to meet demand), involuntary to external stimulus.
- increased HR/BP, constricts blood vessels (chills/sweating), pupils/bronchi dilates, inhibits digestion, decreased saliva and muscles become tense
Functions of nervous system
Detects change/feeling sensations, initiates response to change and organizes/stores change
Parasympathetic division. S/S
Returns body to restful state, regulates involuntary functions (relaxes body)
- slows HR, increases peristalsis (digestion), constricts bronchi/pupils, dilates vessels
Both divisions work together to..
Balance body functions (maintain homeostasis)
Meninges
Connective tissue that covers brain and spinal cord
-DAP
Dura mater (meninges)
Thick outer most layer that lines skull and vertebral canal
Arachnoid membrane (meninges)
Middle layer, web like strains
Pia mater (meninges)
Thin Inner most layer membrane on surface of spinal cord and brain
What contains CSF
Subarachnoid space
CSF is formed in
Ventricles of the brain by CHOROID PLEXUSES (from blood plasma)
CSF circulates from
Ventricles to central canal of spine-cranial/spinal subarachnoid space
CSF’s reabsorbed from
Cranial subarachnoid space through arachnoid villi-blood I CRANIAL VENOUS SINUSES
Rate reabsorption = production
CSF’s functions
Carries nutrients to CNS, removes waste, shock absorber and cushions CNS
Medulla oblongata
Regulates vital functions: HR, BP, breathing. Reflexes of coughing, sneezing, swallowing and vomiting
Pons
Respiratory center that works with medulla
Midbrain
Center for vital reflexes: visual, auditory, equilibrium
Cerebellum
Regulates coordination of voluntary movement. Muscle tone, stopping, movement, posture and equilibrium
Hypothalumus
Regulates body temp
Cerebrum (largest part of Brian)
Cerebral cortex is the surface of gray matter
Frontal lobe
(Motor area) initiate voluntary movement, learned skills, social behavior, speech
Parietal lobe
(Sensory) feels and interprets senses conscious muscle tone, taste, and thought before speech
Temporal lobe
(Auditory) hearing and interpretation. Olfactory (smell and interpretation)
Occipital lobe
(Visual) interpretation for spatial relationship
Central nervous system (CNS)
Brain and spinal cord (controls all body parts)
-sensory, memories and emotions
Peripheral nervous system (PNS)
Cranial/spinal nerves (not in brain or spine)
-brings messages to and from CNS to rest of body
Autonomic nervous system (ANS)
Regulates involuntary activities. ( heart beat, pupil dilation)
*branches to sympathetic and parasympathetic divisions
Receptors
Detect external/internal changes and transmit information to CNS via sensory neurons
Stretch reflex
Stretched muscles automatically contract. (Keeps us upright against gravity)
Flexor reflex
Withdraw reflex from painful stimulus
Reflex arc
Involuntary response to stimulus. (Knee jerk)
Neuron
Is the Cell body that contains nucleus. In CNS
Axon
Carries impulses away from cell body
Dendrites
Carries impulses toward cell body
Myelin sheath
Coating on axon for protection. Conducts electrical impulses (electrically insulates neurons from on another)
Sensory neuron (afferent neuron)
Carry impulses from receptors to CNS (from skin, skeletal muscles, joints and internal organs)
Motor neuron (efferent neuron)
Carry impulses from CNS to effectors. (To skeletal/smooth/cardiac muscles and glands)
Synapse
Space between axon (of one neuron) and dendrite (of another neuron)
Chemical neurotransmitters
(Boat) released by axon
-acetylcholine, epinephrine, norepinephrine, dopamine and seratonin
Chemical Inactivator of Acetylcholine
Cholinesterase
Olfactory
Smell
Trigeminal
Sensation in face
Acoustic
Hearing
Vagus
The rest of the body
Facial
Motor
Spinal cord functions
Transmits impulses to and from brain and integrates spinal cord reflexes
Location of spinal cord
within vertebral canals, to disc between 1st and 2nd lumbar vertebrae
Central canals contain
CSF within ventricles of brain
