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Types of NervesTypes of NervesTypes of Nerves
A network of nerves runs throughout our body. Nerves are of three types, that

are sensory nerves , motor nerves and connecting nerves .

Sensory nerves carry signals from the
sense organs to the spinal cord and

then to the brain. These signals
include smell, temperature, colour etc.
Motor nerves carry message from the

brain and spinal cord to the muscles
and glands. These messages tell the

muscles and glands what to do.

Connecting nerves pass the messages between sensory nerve cells and motor
nerve cells.

REFLEX ACTION

What do you do if you accidently touch a very hot
cup of tea? You withdraw your hand immediately Brain

without even thinking. Such actions that happen
Sensory Carries
automatically without our thinking are called neuron message
reflex actions.

In reflex action, the brain has no role; only the
Spinal cord
spinal cord is involved. When you touch a hot

object, the sensory nerves convey the signal of Signal Passed along
the high temperature (hotness) to the spinal cord. Sensory Neuron

This signal is then passed to the motor nerves through the connecting nerves.

The motor nerves carry the instructions to the muscles of the hand to withdraw
the hand.
Blinking of eyes and withdrawing the foot when you step on a sharp object

accidentally, are other examples of reflex action.
Can you think of some more examples?

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Dolphins have the best sense of hearing among animals. Their hearing is
14 times sharper than in human beings.

THE SENSE ORGANS
The eyes, ears, nose, tongue and skin are our sense organs.

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