Page 280 - New Medley 5 Semester 1

Brain Skull

The brain is the control centre of the body. It is protected Cerebrum

in the bony skull. It is divided into three major parts Cerebellum
— Cerebrum, cerebellum and medulla (brain stem).
Medulla
Cerebrum: It is the biggest part of the brain. It has

many grooves and folds on its surface. It controls our
ability to think, learn, decide, remember, dream and feel. Three main parts of brain

It also receives and interprets information given by our sense organs.
Cerebellum: It controls and organises our voluntary activities such as walking,

running, dancing, painting, etc. It also maintains the balance of the body.

Medulla or brain stem: It joins the spinal cord to the brain. It controls all the
involuntary actions like breathing, heartbeat and muscle movements in the

digestive system.
Brain
Spinal cord

The spinal cord is the extension of the medulla of the

brain. It lies almost up to the lower end of the vertebral Nerves
column. It is protected by the vertebral column. It

receives information from sense organs and passes it Spinal
cord
to the brain and in turn sends orders from the brain

to sense organs.

Nerves Spinal cord connected with brain

All parts of the nervous system are formed of nerve Dendrite
cells or neurons. Nerves are the bundles of nerve cells that

spread throughout the body like a network of telephone Cell body
cables. Each nerve cell has a cell body. Small fibres called

dendrites extend out from the cell body. A long fibre called
axon extends from one end of the cell body. Axon

Nerves carry signals to and from the spinal cord and the

brain. They connect
the brain and spinal Knowledge Zone

cord to all the parts The human body contains approximately
of the body. 100 billion nerve cells, about half of A nerve cell
which are found in the brain.

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