NERVOUS SYSTEM NERVOUS SYSTEM

Karen LancourKaren Lancour Patty PalmiettoPatty PalmiettoNational Bio Rules National Bio Rules National Event National EventCommittee Chairman Committee Chairman Supervisor – A&P Supervisor – A&P

Divisions of the Nervous Divisions of the Nervous SystemSystem

Brain Brain

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Spine Spine

Rest Rest of of BodBody y

NeuronNeuron

Basic functional cell of nervous system

Transmits impulses Three types

Sensory neurons – bring messages to CNS Motor neurons - carry messages from CNS Interneurons – between sensory & motor

neurons in the CNS

NeuronNeuron

Dendrite – receive stimulus and carries it impulses carries it impulses toward the cell bodytoward the cell body

Cell Body with nucleus – nucleus & most of cytoplasm Axon – fiber which carries impulses away from cell carries impulses away from cell

bodybody Schwann Cells- cells which produce myelin or fat layer Myelin sheath – lipid layer around the axon Node of Ranvier – gaps or nodes in the myelin sheath Impulses travel from dendrite to cell body to axondendrite to cell body to axon

ImpulsesImpulses

Impulse Self propagating Mechanism – Na+

K+ pump Synapse

Junction between neurons

Neurotransmitters

SynapsSynapse e

Junction between neuronsJunction between neuronsThe neurons do not actually tough at the The neurons do not actually tough at the synapse synapse Neurotransmitters used to restart impulse Neurotransmitters used to restart impulse in dendrite of 2in dendrite of 2ndnd neuron neuron

NeurotransmittersNeurotransmitters

Chemicals in Chemicals in the junction the junction which allow which allow impulses to impulses to be started in be started in the second the second neuron neuron

Reflex Arch Reflex Arch

Central Nervous Central Nervous SystemSystem

Brain Brain stem –

medulla, pons, midbrain

Diencephalon – thalamus & hypothalamus

Cerebellem Cerebrum

Spine Spinal Cord

Cerebrum Regions Cerebrum Regions

Lobes of the Cerebrum Frontal Parietal Temporal Occipital

Special regions Broca’s area Wernicke’s area Limbic System

Peripheral Peripheral Nervous Nervous System System

Cranial nervesCranial nerves 12 pair 12 pair Attached to Attached to

undersurface of undersurface of brainbrain

Spinal nervesSpinal nerves 31 pair31 pair Attached to spinal Attached to spinal

cordcord

Autonomic Nervous Autonomic Nervous System System

Regulates bodies involuntary Regulates bodies involuntary responsesresponses

Two divisionsTwo divisions Sympathetic nervous systemSympathetic nervous system

Emergency responseEmergency response Fight or flight Fight or flight

Parasympathetic nervous systemParasympathetic nervous system Normal everyday conditions Normal everyday conditions

Autonomic Nervous Autonomic Nervous System System

Major Sense OrgansMajor Sense Organs

Vision – Eye Hearing – Ear Taste – Taste receptors (new) Smell – Olfactory system Skin – Hot, cold, pressure, pain

EyeEye

ImagesImages

the cornea and the lens help to produce the image on the the cornea and the lens help to produce the image on the retina retina images formed by the lens are upside down and images formed by the lens are upside down and backwards whenbackwards when they reach the retinathey reach the retina

Visual Pathway Visual Pathway

EaEarr

Taste BudsTaste Buds

Chemical Receptors Sweet Sour Bitter Salty MSG

Olfactory ReceptorsOlfactory Receptors

Chemical Receptors Top of nasal cavity Extremely sensitive Easily fatigued Much of “taste” involves smell

SensesSensesin Skinin Skin

Heat Cold Light

pressure Heavy

Pressure Pain

Disorders of the Disorders of the Nervous SystemNervous System

Epilepsy, Epilepsy, Seizures, Seizures, Alzheimer’s DiseaseAlzheimer’s Disease Multiple SclerosisMultiple Sclerosis Parkinson’s Disease, Parkinson’s Disease, Shingles (herpes zoster), Shingles (herpes zoster), Cerebral palsy, Cerebral palsy, Glaucoma, Glaucoma, Pink eye (conjunctivitis)Pink eye (conjunctivitis) Symptoms of disordersSymptoms of disorders Treatments and prevention Treatments and prevention

Effects of Drugs Effects of Drugs

Effects of drugs on the Effects of drugs on the nervous systemnervous system

AlcoholAlcohol CaffeineCaffeine NicotineNicotine MarijuanaMarijuana