Question

Select the correct option about ribs.

• A. 8th, 9th and 10th pairs of ribs articulate directly with the sternum.
• B. 11th and 12th pairs of ribs are connected to the sternum with the help of hyaline cartilage.
• C. Each rib is a flat thin bone and all the ribs are connected dorsally to the thoracic vertebrae and ventrally to the sternum.
• D. There are seven pairs of vertebrosternal, three pairs of vertebrochondral and two pairs of vertebral ribs.

Answer 1

The correct option is D

There are seven pairs of vertebrosternal, three pairs of vertebrochondral and two pairs of vertebral ribs.

The correct option is D.

Explanation of the correct option:

Option D:

1. Vertebrosternal ribs are the ribs that connect thoracic vertebrae to the manubrium and sternum.
2. Ribs are flat bony framework of the thoracic cavity.
3. The vertebrosternal ribs include ribs 2 to 6 or 7.
4. The vertebrochondral ribs include ribs 8 to 12, these ribs are connected to the sternum indirectly via the rib cartilages (connective tissue).
5. Hence, there are 10 pairs of true ribs.

Explanation of the incorrect options:

Option A:

1. The 8th, 9th, and 19th pairs of ribs are connected to the sternum via rib cartilage.
2. They are not connected directly with the sternum.
3. This is an incorrect option.

Option B:

1. The 11th and 12th pairs of ribs are free-floating ribs.
2. They are also called false ribs as they are not connected to the sternum.
3. This is an incorrect option.

Option C:

1. This is an incorrect option as not all ribs are connected to the sternum.
2. Free-floating ribs (11th and 12th pairs of ribs) are false ribs that are not connected to the sternum.

Final answer: The correct option about ribs is that there are seven pairs of vertebrosternal, three pairs of vertebrochondral, and two pairs of vertebral ribs.