Question

Assertion: The 8th, 9th and 10th pairs of ribs are called false ribs
Reason: They are not directly attached to the sternum

• A. Both assertion and reason are true and reason correctly explains assertion
• B. Both assertion and reason are true but reason is not the correct explanation of assertion
• C. Assertion is true but reason is false
• D. Both assertion and reason are false

Answer 1

The correct option is A Both assertion and reason are true and reason correctly explains assertion

There are 12 pairs of ribs. The first 7 ribs are dorsally attached to the thoracic vertebrae and ventrally attached to the sternum with the help of the hyaline cartilage. They are called true ribs. The 8th, 9th and 10th pairs of ribs are attached to the 7th pair of ribs with the help of hyaline cartilage. They do not directly articulate to the sternum and are therefore called false or vertebrochondral ribs. The 11th and 12th pairs of ribs are not connected ventrally and are therefore, called floating ribs.