RAYAT SHIKSHAN SANTHA’S KANYA VIDYALAYA DEHU

Ppt on : Control & coordination By Sucheta Khindkar

EVOLUTION OF NERVOUS SYSTEM

FROM BRAIN STEM TO CEREBRUM

FUNCTIONS OF NERVOUS SYSTEM To receive Information from a sensory neuron. To process info. by the brain and spinal cord. To respond by the effectors {muscle/glands} t To receive information

Acupuncture:Stimulation of nerve centers

Functions of nervous system Sensory input : Gathering information. To monitor changes occuring inside and outside the body. Integration: To process and interpret sensory input & decide if action is needed. 3.Monitor output: A response to integrated stimuli. The response activates muscles or glands.

Structural classification of nervous system Central Nervous System {CNS} Brain Spinal cord 2. Peripheral Nervous System{PNS} Nerve outside the brain and spinal cord

Nervous Tissue: Support Cells (Neuroglia or Glia) Astrocytes Abundant, star-shaped cells Brace neurons Form barrier between capillaries and neurons Control the chemical environment of the brain (CNS)

The basic unit of the nervous system = neuron? Dendrites receive stimuli Nerve cell body @ nucleus transmits the stimuli Axon transmits the impulse to another dendrite

Neuron

Nervous Tissue: Neurons Neurons = nerve cells Cells specialized to transmit messages Major regions of neurons Cell body – nucleus and metabolic center of the cell Processes – fibers that extend from the cell body (dendrites and axons) Slide 7.8 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Axon Ending : Terminal Bud Transfers the electrical nerve impulse By chemical neuron-transmitters From one neuron to the next

Two connecting Neurons

Nervous Tissue: Support Cells Microglia (CNS) Spider-like phagocytes Dispose of debris Ependymal cells (CNS) Line cavities of the brain and spinal cord Circulate cerebrospinal fluid Figure 7.3b, c Slide 7.6 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Support Cells of the PNS Satellite cells Protect neuron cell bodies Schwann cells Form myelin sheath in the peripheral nervous system Figure 7.3e Slide 7.7b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Application In Multiple Scleroses the myelin sheath is destroyed. The myelin sheath hardens to a tissue called the scleroses. This is considered an autoimmune disease. Why does MS appear to affect the muscles?

Neuron Classification Figure 7.6 Slide 7.15 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

aSensory neurons or“receptors” receive a stimulus from: eyes - sight ears - hearing nose - smell skin - touch mouth - taste

The central Nervous System {CNS} Spinal cord Brain Medulla for Breathing. Cerebellum for Balance Cerebrum for Higher thinking

2c. Effectors that do actions are the Muscles = voluntary use the somatic system involuntary use autonomic system Glands = endocrine organs that make hormone messengers

Cerebral Cortex= higher thinking

Parts of the Cerebrum

Cerebellum & “old brain” controls basic body functions

Right versus left Cerebrum

Infrared Tools to Study the brain . . . .

Schizophrenia & a normal brain scan

Any blow to the head does brain damage Example of amnesia & processing skills

D. What is a synapse ? Junction of two neurons Neurotransmitters convert the electrical impulse into a chemical message

E. The 2 types of nervous responses? a. Voluntary that use the brain & spinal cord b. Involuntary or Autonomic System Sympathetic Parasympathetic

The involuntary system: Autonomic basic body functions & reflex arcs

The Autonomic Nervous System

REVIEW: The Autonomic Nervous System... Automatic Two parts: parasympathetic & sympathetic Which is “fight or flight response” ? Which is ordinary involuntary body functions ?

E2. Involuntary Reflex Arcs . . . . Use only spinal cord Do not go to the brain Follow the R-SIM pathway Examples: knee jerk, eye blink, hot stove pull back

R-SIM Reflex arc pathway . . . receptor neuron receives the stimuli S sensory neuron passes the impulse on I interneuron at the spinal cord processes M motor neuron acts

Is Pain part of the Reflex Arc ???

The five types of receptors Are highly specialized Receive only one type of stimuli Can be “overloaded” when over stimulated

Sensory Laboratory. . . . . . . . . PURPOSE: Map the distance between touch receptors Measure the extent of peripheral vision Determine the effects of cone saturation Map the taste receptors Measure reflex timing

Map of Taste Receptors . . . . B w

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