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Did You An average baby’s brain is around ¼ of the size of an adult’s brain. It doubles in size
Know? within its first year. It continues to expand, reaching around 80% of adult size by the age
of three and 90% by the age of five. The adult human brain weighs approximately 1.5
kg. The brain contains 60% fat and 40% water, protein, carbohydrates, and salts.

Lungs

The lungs are two air-filled sacks located inside
our chest on both sides. They are protected by Nose

the ribcage. The air or oxygen we breathe through Ribcage Wind Pipe

our nose goes to the windpipe, which carries it

into our lungs. Lungs help us breathe.

The tiny hair inside our nose filters the air that

enters our body. So, the lungs get air rich in

oxygen. When we breathe air into the lungs,

it is called inhalation. The lungs expand when

we inhale. When we breathe out air it is called
Lungs
exhalation. The lungs contract when we exhale.
Find It Who is a Pulmonologist?
Out
Heart When do we visit him?

The heart circulates blood throughout our body through fine tubes known as

blood vessels. It works all day and night to keep us alive.

We can feel our heartbeats by laying our palm on the left side of our chest. Our

heart beats around 72 times each minute.

The heart is a reddish-brown coloured

muscular organ. It is as big as our fist.

The heart is located in a slanting position
Left atrium
in the center of our chest. It has four
Right chambers. The two chambers on the upper
atrium
Left ventricle side of the heart are called the atria. The
Right two chambers on the lower side of the heart
ventricle
are called ventricles. Blood flows through

Heart all the four chambers of the heart.

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