health science unit 10

CNS

Brain and spinal cord

Peripheral Nervous System

Cranial and spinal nerves

Autonomic Nervous System

Peripheral nerves and ganglia

CNS

Responsible for communication and coordination system of the body; Center of intellect and reasoning

Brain

3 lbs mass of nervous tissue; Dividing into 4 parts

Cerebrum

Largest part of the brain; Responsible for higher level of thinking

Myelin sheath

Protects axon; Sends faster impulse; On white matter

Frontal Lobe

Motor area that controls voluntary muscles; Speech area is located in L hemisphere

Parietal Lobe

Sensory area that receives and intercepts messages from the pain, touch, heat, and cold receptors;Helps in determining perception

Occipital Lobe

Controls vision and eyesight

Temporal Lobe

Auditory and olfactory areas; hear and smell

Dura Mater

Outer brain covering, lines inside of skull; Tough, dense fibrous connective tissue

Subdural Space

Between dura and arachnoid space

Arachnoid

Middle layer; Resembles fine cobweb

Pia Mater

Covers the brain surface, made of blood vessels held together by connective tissue

Subarachnoid Space

Between arachnoid space and pia mater, filled with CSF

Cerebral Spinal Fluid

Acts as a shock absorber and source of nutrients; Bathes brain and spinal cord

cerebral ventricles

Brain contains 4 cavities filled with CSF

Choroid Plexus

Network of blood vessels lining ventricles which help in formation of CSF

Blood Brain Barrier

Choroid plexus capillaries prevent substances from pentrating brain tissue--this makes infections like meningitis difficult to cure

Lumbar Puncture

Removal of CSF from spinal canal--Needle puncture between 3rd and 4th lumbar vertebrae

Limbic System

Located in the center of the brain; Encircles the top of the brain stem

Diencephalon

Thalamus--spherical mass of gray matter; deep in cerebral hemisphere; Controls consciousness

Hypothalamus

Lies below the thalamus, part of limbic system

Pineal

Endocrine system gland; effects mood depending on light

Pituitary Gland

Endocrine system gland

Hypothalamus

ANS; Temp. Control; Appetite Control; Emotional State; Sleep control

Cerbellum

Located behind the pons below the cerebrum; Controls all body functions related to skeletal muscles; Balance, Muscle Tone, Coordination, Muscles Movement

Brain Stem

Pathway from brain to body; Made of pons, medulla, and mid brain; Pathway for ascending and descending tracts of nerve pathways

Pons

In front of cerebellum, between midbrain and medulla- Contains center that controls respiration

Midbrain

Visions and hearing

Medulla Oblongata

Bulb-shaped structure between pons and spinal cord; Inside that cranium above foramen magnum; Responsible for heart rate and blood pressure

Neuron

Transmits a message from one cell to the next; Nerve cell

Dendrites

Carries impulse to cell body; May be one or many

Axon

Carries impulse away from cell body; Only one on a neuron

Neurilemma

Myelin Sheath; Covering that speeds up the nerve impulse along the axon

Synapse

Space between neurons, messages go from on cell to the next

Nerve Impulse

A stimulus creates an impulse, travels into the neuron on the dendrite and out on the axon, neurotransmitter released that carries impulse across the synapse to the next dendrite

Spinal Cord

Begins at foramen magnum and continues down to 2nd lumbar vertebrae; White and soft, in spinal canal; Surrounded by CSF; Reflex center; Pathway to and from brain

Peripheral Nervous System

All the nerves of the body and ganglia; ANS is a specialized part of the PNS

Spinal Nerves

Originate at the spinal cord and go through opening in the vertebrae; 31 pairs; Named in relation to location

Cranial Nerves

Begin in the brain; 12 pairs of cranial nerves; Designated by number and name

Autonomic Nervous System

Regulates activities of visceral organs; All body organs we can't control

Sympathetic Nervous System

The fight or flight system; When body perceives danger, SNS sends message to adrenal medulla to secrete adrenaline- heart beat increases

Parasympathetic Nervous System

This counters effects of SNS, and decreases heart rate

Somatic Nervous System

Nerves located along spinal cord; Connect skeleton, muscles and joints to the brain

Meningitis

Inflammation of the lining of the brain and spinal cord; May be bacterial or viral; Fever and stiff neck; May lead to paralysis and death; Antibiotics

Encephalitis

Inflammation of the brain caused by chemicals or virus; Extreme weakness and visual disturbance

Cerebral Palsy

Disturbance in voluntary muscular activity caused by brain damage; Spastic paralysis due to birth inquiry

Poliomyelitis

;Virus; Rarely seen in US since 50's; Disease of nerve pathways causes paralysis; Vaccine available; One of biggest cause of death in the past

Epilepsy

Seizure disorder of the brain, characterized by recurring and excessive discharge from neurons; Seizures believed to be result of spontaneous uncontrolled activity of neurons; Uncertain cause

Grand Mal

Severe conclusive seizure

Petit Mal

Milder (Staring into space)

Alzheimers

Progressive disease; Begins with memory problems

Hydrocephalus

Increase in volume of CSF in the ventricles of the brain caused by a blockage in the 3rd or 4th ventricle; Leads to enlarged head; Can cause mental impairment; Shunt used to drain

Parkinson's Disease

Characterized by symptoms of shuffles gait and trembling; May be caused by decrease in neurotransmitter- dopamine; Can be caused by constant hits to the head

Multiple Sclerosis

Occurs when the myelin sheath around the axon is destroyed; Slows nerve impulses causing loss of muscle coordination; Immune response attacks and destroys myelin

Cerebral Vascular Accident

Stroke; Interruption of blood and oxygen to brain; Tissue death; 3rd leading cause of death; Smoking, hypertension, heart disease, family history; 90% caused by blood clots- lodge in arteries blocking blood flow to the brain; 10% caused by rupture

West Nile Virus

Disease process in subtropical areas; Vector borne; Flu-like symptoms; Warm areas, no cure; Treat symptoms

arach

spider

cephal

head

cerebell

cerebellum

cerebr

cerebrum

crani

skull

encephalo

brain

endo

within

esthesia

sensation, feeling

graph

instrument used to record an image

hemi

half

hydro

water

mening

membrane covering the brain

myel

spinal cord

neuro

nerve

oid

like, resemble

pleg

paralysis

psych

mind

us

structure

Blood-brain barrier

inability of some substances to penetrate the brain tissue

Cerebral Ventricles

four cavities within the brain that are filled with cerebrospinal fluid

Convolutions

elevated folds on the surface of the cerebrum that increase the surface area of the brain

CVA

cerebrovascular accident; stroke

dementia

loss in at least two areas of complex behaviors

fight or flight response

body perceives danger and prepares to run away or stand and fight; heart rate increases, mouth becomes dry, and pupils and bronchi dilate

gyri

convolutions in the brain

lumbar puncture

a needle is inserted between two vertebrae to remove a sample of cerebrospinal fluid

Neurotransmitter

a chemical messenger that carries, boosts, and balances signals between neurons (ex. Acetylcholine)

Paralysis

the loss of the ability to move (and sometimes to feel anything) in part or most of the body, typically as a result of illness, poison, or injury

stimulus

something that can elicit or evoke a physiological response in a cell, a tissue, or an organism

foramen magnum

Where does the spinal cord begin?

associative

neuron that sends information between sensory and motor neurons

interneurons

another word for associatve neurons

motor

neurons that send information from central nervous system back to body

longitudinal fissure

Deep groove that divides cerebrum

temporal

hearing, facial recognition

parietal

pain, touch, heat, and cold

frontal

emotions, personality, morality, intellect, speech, smell

diencephalon

located between cerebrum and midbrain

limbic system

located in the center of the brain

limbic system

surrounds the brain stem

limbic system

includes the hypothalamus, hippocampus, amygdala