Question

With respect to rib cage, explain the following:
a.Bicephalic ribs
b.True ribs
c.Floating ribs

Answer 1

Bicephalic ribs

In humans, there are 12 pairs of ribs present. Most of the ribs are attached ventrally to the sternum and dorsally to the vertebral column. At the dorsal end of the ribs, there are two articular surfaces. Hence bicephalic ribs.



True ribs

There are 12 pairs of ribs present in human beings. Most of the ribs are attached ventrally to the sternum and dorsally to the vertebral column. Based on this, the ribs are divided into three types; true ribs, false ribs, and floating ribs.
The first seven pairs of ribs are called the true ribs.They are attached to the sternum through the costal cartilage. Whereas the other three pairs do not attach ventrally to the sternum. The 8${}^{\text{th}}$, 9${}^{\text{th}}$ and 10${}^{\text{th}}$ ribs attached to the 7${}^{\text{th}}$ rib ventrally are called false ribs. Whereas 11${}^{\text{th}}$ and 12${}^{\text{th}}$ pairs are not attached to the sternum nor the 7${}^{\text{th}}$ rib ventrally, thus are called floating ribs.

Floating ribs

There are 12 pairs of ribs, out of which the first seven pairs of ribs are called the true ribs. They are attached to the sternum through the costal cartilage. Whereas the other three pairs do not attach ventrally to the sternum. The 8${}^{\text{th}}$, 9${}^{\text{th}}$ and 10${}^{\text{th}}$ ribs attached to the 7${}^{\text{th}}$ rib ventrally are called false ribs.
Whereas 11${}^{\text{th}}$ and 12${}^{\text{th}}$ pairs are not attached to the sternum nor the 7${}^{\text{th}}$ rib ventrally, thus are called floating ribs.