Which of the following is incorrect about ribs? (a) Each rib is a thin and cat bone connected dorsally to the vertebral column and ventrally to the sternum. (b) Ribs has two articulation surfaces on its dorsal end which are called bicephalic. (c) Ventrally ribs are connected to sternum by elastic cartilage. (d) First 7 pairs are called true ribs. The 8,9 and
pair is known as false (vertebracondral) ribs and the 2 pairs (11″ and
) are known as floating ribs.
The Correct Answer and Explanation is:
Correct Answer: (a) Each rib is a thin and cat bone connected dorsally to the vertebral column and ventrally to the sternum.
Explanation:
Option (a) is incorrect because it contains a factual and typographical error. The term “cat bone” is incorrect and confusing in this context. Ribs are not described as “cat bones.” They are long, curved flat bones that form the rib cage. This mistake makes the statement scientifically inaccurate.
Here’s a breakdown of the other options, which are correct:
(b) Ribs have two articulation surfaces on their dorsal end, and this is referred to as being bicephalic (bi = two, cephalic = head). This allows the rib to articulate with the bodies of two adjacent thoracic vertebrae and the transverse process of the lower vertebra.
(c) The ventral end of the ribs is connected to the sternum by costal (elastic) cartilage. This cartilage provides flexibility to the thoracic cage, allowing for expansion during breathing.
(d) Ribs are categorized as:
- True ribs (1st to 7th pairs): These are directly attached to the sternum by their own costal cartilages.
- False ribs (8th to 10th pairs): These do not attach directly to the sternum. Instead, their cartilages are joined to the cartilage of the rib above them. They are also called vertebrochondral ribs.
- Floating ribs (11th and 12th pairs): These are not connected to the sternum at all, not even indirectly. They are only attached dorsally to the vertebral column, making them floating.
Understanding the classification and structure of ribs is essential in anatomy and physiology because it relates to vital functions such as breathing and protection of the thoracic organs.
