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Module 9
Science and Health
PARTS OF THE BRAIN AND THEIR FUNCTIONS
A DepEd-BEAM Distance Learning Program supported by the Australian Agency for International Development
To the Learner
The brain is responsible for issuing nerve impulses, processing
nerve impulse data, and engaging in the higher order thought
processes. It is the master control center over the body.
Let’s Learn This
Identify the parts of the nervous system and their functions.
Let’s Try This
HOW GOOD IS YOUR MEMORY?
1. Read the three columns for one minute. Try to remember the
syllables and words in the three columns.
Column 1
han
shi
phi
cho
aug
fat
gre
pla
Column 2
heating
greater
together
function
east
ability
party
shop
Column 3
Your
Brain
Can
Easily
Retain
Short
Understandable
messages
2. Recall as many syllables and words as you can and write them
down in your paper.
3. How many syllables in column 1 and words in column 2 & 3 do
you remember correctly?
________________________________________________________________
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4. Which syllables and words in the three columns are difficult to
recall?
________________________________________________________________
5. Which column is the easiest to recall?
________________________________________________________________
6. What do you think affects your ease of recall?
________________________________________________________________
Let’s Study This
The brain is divided into three parts: the large cerebrum, the
smaller cerebellum, and the brainstem leading to the spinal cord.
I.
The Cerebrum
The cerebrum or forebrain forms the bulk of the brain. It is
a large mass of white and gray neural fiber in the upper cranium.
It is responsible for the higher thought processes such as
memory, judgment, and reason. It also processes sensory data
initiating willful motor processes, such as voluntary muscle
bending.
The
cerebrum
is
composed of two lateral
halves called the right
and the left cerebral
hemispheres. They feature
a number of folds called
gyri and furrows called
sulci. They are connected
in the middle at the
medulla.
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II.
The Cerebellum and How It Functions
The cerebellum is the
second smaller division of
the brain. It is located below
the cerebrum and in the back
part of the cerebrum. It
consists of large mass folia.
It also has a right and a left
hemisphere, and a finger-like
structure in the middle.
The
cerebellum
is
responsible for body balance,
posture,
and
the
coordination of movement.
Nerve pathways connect
the
right
half
of
the
cerebellum with the left
cerebral hemisphere and the
right side of the body.
Pathways from the left half
connect
with
the
right
cerebral hemisphere and the
left side of the body.
The cerebellum receives, coordinates, and modifies orders from
the cerebrum. For example, to be able to maintain precise muscular
coordination, this is what happens. First, the cerebellum receives
information about body balance and equilibrium from nerve endings in
the inner ear. Then, the cerebellum adjusts and fine tunes these
actions by passing the regulating signals to the motor neurons of the
brain and spinal cord. Thus, the person moves and acts normally.
If the cerebellum is damaged, the person will have loss of ability
to maintain precise muscular coordination and fine cooperative actions
of the motor processes. This disease is called ataxia.
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III.
The Brain Stem and Other Structures
The brain stem is located behind
the cerebellum. It is a stalklike
structure that connects the cerebrum
with the spinal cord.
The bottom part of the brain
stem is called the medulla oblongata.
Just above the medulla is the pons.
Above the pons lies the midbrain.
The pons connects the two
hemispheres of the cerebellum. Its
nerve fibers link the cerebellum and
the cerebrum.
Nerve centers in the midbrain
help control movements of the eyes
and the size of the pupils.
Thalamus, Hypothalamus, and Reticular Formation
At the upper end of the brain stem are the hypothalamus and the
thalamus. One thalamus is on the left side of the brain stem. Another
thalamus is on the right side. Each thalamus receives nerve impulses
from various parts of the body and redirect them to the appropriate
areas of cerebrum. They also relay impulses from one part of the brain
to another.
The hypothalamus regulates internal conditions of the body such
as temperature, hunger, pain, pressure, etc. Beside the hypothalamus
is the pituitary gland which is the master gland of the body. It is the
hypothalamus which controls the activity of the pituitary gland.
The reticular formation is a network of nerve fibers. It lies deep
within the brain stem. It helps regulate and maintain the brain’s level
of awareness. It is stimulated by the sensory messages that pass
through the brain stem. The reticular formation stimulates alertness ad
activity throughout the cerebral cortex.
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Let’s Do This
1. Observe and take note of what the members of your family are
doing for about 5-10 minutes.
2. Write your observations in your paper. Identify the parts of the
brain responsible for each of the actions they do.
3. Your chart should look like this.
Members of
the Family
Actions
Parts of the brain
responsible
1. ______________
_____________________
_____________________
_____________________
_____________________
2. ______________
_____________________
_____________________
_____________________
_____________________
3. ______________
_____________________
_____________________
_____________________
_____________________
4. ______________
_____________________
_____________________
_____________________
_____________________
4. What part of the brain do they commonly use?
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Let’s Do More
Answer the following:
Parts of the brain
Functions of each part
Parts of the Brain
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Let’s Remember This
The brain is the master organ of the nervous system and the
control center of the body. It receives information about the
outside world from your senses and sends out messages to tell
your body what to do. Its main parts are: cerebrum, cerebellum,
and brainstem. The cerebrum enables you to think, memorize,
recognize and be aware of the things happening in your
surroundings. It receives and interprets the messages of the five
senses. The cerebellum coordinates voluntary muscular actions. It
is responsible for the ability to learn habits and develop skills. It
also maintains balance in the body. The brainstem controls
involuntary actions such as breathing, alertness, and eye
movement. It conveys messages between the spinal cord and the
brain. It also takes care of the reflex actions such as coughing and
blinking.
Let’s Test Ourselves
Choose the letter of the correct answer.
1. What controls the involuntary actions of the body?
A. nerves
B. cerebrum
C. cerebellum
D. brainstem
2. Which is the largest part of the brain and it controls mental
processes such as thinking, memorizing, and decision-making?
A. pons
B. cerebellum
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C. cerebrum
D. spinal cord
3. What coordinates voluntary muscular actions and maintains
balance in the body?
A. cerebrum
B. cerebellum
C. brainstem
D. spinal cord
4. Why is the brain enclosed in the skull?
A. for
B. for
C. for
D. for
design
protection
a better look
sound proofing
5. What will happen if a person injures part of his brain? The person
______________.
A. will die
B. brain decays
C. actions will continue to be coordinated
D. cannot integrate and coordinate his movements
Science Fact File
The hypothalamus forms the main link between the body’s
endocrine system and nervous system. However, some endocrine
glands are not controlled by the pituitary gland or by the nervous
system. These are the glands that help maintain the normal chemical
composition of the blood and respond to changes in the amounts of
various chemicals.
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Answer Key
Let’s Try This
Answer depends on the learner’s memory
Let’s Do This
Answers depend on the actions of the different members of the
family
Let’s Do More
Parts of the Brain
Cerebrum
Enables us to:
think, memorize
and recognize.
Cerebellum
Coordinates
voluntary
muscular actions.
Ability to learn
habits
and
developed skills.
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Brain Stem
Controls
involuntary
actions such as
breathing,
alertness and eye
movement.