Question

The number of false ribs is
A. 2
B. 3
C. 4
D. 7

Answer 1

Hint: Human skeletal system consists of the bones, cartilages and ligaments. They serve the purpose of support and give shape to the body. Ribs are part of the skeletal system which are 12 pairs in number. Each rib is a semi-circular, flattened bone that contributes to the wall of the thorax. The ribs may be true, false or floating ribs.

Complete answer:
Altogether the axial skeleton of the human adult consists of 80 bones. It includes all the bones of the skull, the vertebral column and the thoracic cage.
The appendicular skeleton consists of all bones of the upper and lower limbs. Besides the bones of limbs, the appendicular also includes the bones that attach each limb to the axial skeleton.
The appendicular skeleton of a human adult has 126 bones.
The rib cage is the part of the axial skeleton that forms the chest of the body. The rib cage consists of 12 pairs of ribs with their costal cartilages and the sternum.
The first seven pairs are called true ribs because they are directly attached to the sternum. Eight, ninth and tenth pairs are not directly attached to the sternum, instead they are joined to the pair number 7. So, they are called false ribs. The last two pairs of ribs are called floating ribs because their anterior ends are not attached either to the sternum or the cartilage of another rib. The last two pairs of ribs protect the kidneys.

Thus, option B. 3 pairs is the correct answer.

Note: Ribs pair 1 to 7 are vertebra-sternal ribs. The costal cartilage from each of these ribs attaches directly to the sternum. Ribs 8 to 12 are not directly attached to the sternum. For ribs 8–10, the costal cartilages are attached to the cartilage of the next higher rib.
Ribs pair 1 to 7 are vertebra-sternal ribs. Each of these ribs are directly attached to the sternum. Ribs 8 to 12 are not directly attached to the sternum. For ribs 8–10, the costal cartilages are attached to the cartilage of the next higher rib.