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Coordination in animals

The central nervous system (CNS) is the part portion of the central nervous system. It is
of the nervous system consisting primarily delicate and it encased in the skull where
of the brain and spinal cord. The CNS is it is protected by the cranium as shown
named so because it processes the received in Figure 2.8. The brain is housed in a
information, coordinates and influences system of membranes called meninges.
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the activities of all parts of the body. It is The human brain enables a person to
composed of a mass of nerves. The central think or reason and perform complex
nervous system analyses impulses received physical and mental activities. The brain
and determines what actions should be also coordinates simple reflex actions.
taken in response to stimuli. The spinal A reflex action is a rapid and automatic
cord serves as an impulse-conduction response to a stimulus. Generally, the
pathway. Nerve impulses transmitted by functions of the brain include, receiving
the spinal nerves are relayed to the brain. impulses from all sensory organs of the
Nerve impulses from the brain are sent body, interpreting the message, sending
to the spinal cord. From the spinal cord, off motor impulses to glands and muscles
impulses are transmitted to the effector and storing information. It also associates
organs. various stimuli from different sense
organs. The association centres and motor
The brain areas coordinate body activity so that the
The human brain is a specialized organ mechanical and chemical actions of the
that is responsible for coordinating the body work efficiently. The mammalian
functions of the human body. The brain brain consists of three main parts; the fore
also stores memory. It makes up the largest brain, the mid brain and the hind brain.

Cerebrum (fore brain) Skull

Cerebral hemisphere

Meninges Cerebrospinal fluid
Midbrain
Hypothalamus

Cerebellum
Pituitary gland
Hindbrain
Medulla
Spinal cord oblongata

Figure 2.8: Structure of the human brain

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