Page 35 - Active Science 5 Ebook and Activity

called the vertebral column. These 33 small bones help us in turning, twisting
and bending. Due to these, our body remains upright. The backbone encloses and

protects the spinal cord which is connected to the brain.

3. The Ribcage: When you touch your
chest, you feel a frame of bones. It is
known as the ribcage. There are 12 Sternum
pairs of ribs of long curved bones.

Ribcage also protects lungs and heart.
Ten pairs of these ribs are connected to
the breast bone called sternum. The

last two pairs of ribs which are not Floating Ribs
connected to the breast bone are called
floating ribs. Ribcage

4. The Limbs: There are two pairs of
limbs – arms and legs. Pair of arms is Humerus Femur

known as forelimbs and pair of legs
is known as hindlimbs. Humerus is
the long bone in the arm and femur
is the thigh bone in the leg. Femur is

the longest bone in the body. There are
many small bones in our hands, wrists
and ankles.
Arm
Leg

Let’s Recapitulate

Match the following.

1. Skeleton a. 33 bones
2. 206 b. brain

3. Skull c. sternum
4. Vertebral column d. humerus
5. Ribcage e. framework of bones

6. Limbs f. bones

Activity 3.1

Run your fingers along the central portion of your back and feel the small bones of the spine,
arranged in a sequence. Try and count how many bones there are.

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Active Science-5