Transcript 5. Electrical Signals

Human nervous system
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Standard:
9.10.3 Know the general structure and
functions of the human nervous system, the
structure and function of types of nerve
cells, and the pathways taken by a nerve
impulse in response to a stimulus.
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Objectives
1.
2.
3.
4.
5.
Understand the human nervous system.
Determine the structure of the neurons.
Realize that nervous system composed of neurons.
Realize that central nervous system concept.
Identify the types of nervous cells that connected
with CNS.
6. Draw diagrams of sensory and motor nerve cells
and to label each part of the cell.
7. Compare between sensory and motor nerve cells.
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Vocabulary
• Nervous system: (the network of nerve cells and fibers which
transmits nerve impulses between parts of the body)
• Neurons: (a specialized cell transmitting nerve impulses)
• Nerve cells: (cell which is part of the nervous system, neuron)
• Spinal cord: (the cylindrical bundle of nerve fibres which is
enclosed in the spine and connected to the brain, with which it
forms the central nervous system)
• Central nervous system (CNS): system of the body that
includes the brain and spinal cord.
• Sensory nerve cells: (nerves that receive sensory stimuli,
such as how something feels and if it is painful)
• Motor nerve cells: (A neuron that conveys impulses from the
central nervous system to a muscle, gland, or other effector
tissue)
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Starter activity
• Show the next video on nervous player at
football game:
Click here
• At video in your opinion why the French
player push the Italian player?
• Can we called French player nervous
player?
• So what is the topic of our lesson?
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What are neurones?
Neurones are specialized cells that conduct
electrical impulses through the body.
A nerve is a bundle of many nerve
fibres enclosed within a protective
sheath.
nerve
nerve fibre
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What is the central nervous system?
The central nervous system (CNS) is made up of the brain
and spinal cord.
nerve impulses
are relayed
through the
spinal cord and
processed in
the brain.
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What do neurones look like?
Neurones are elongated cells consisting of a cell body and
long, thin axon.
dendrites
myelin
sheath
cell
body
axon
Thin projections called dendrites extend from the cell body
and connect with other neurones, allowing electrical impulses
to pass from one to the other.
The axons of most neurones are wrapped in an insulating
lipid layer called the myelin sheath. Why is this important?
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What are sensory neurones?
Sensory neurones transmit messages from sense
receptors, such as the eye or nose, to the brain or spinal
cord.
cell body
nerve impulse
from sense organ
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nerve impulse
to CNS
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What are motor neurones?
Motor neurones transmit messages from the brain and
spinal cord to the muscles and glands.
cell body
muscle
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Sensory and motor nerve cells
construct a table to show differences between
sensory and motor nerve cells.
Similarities
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Differences
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