THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -In humans there are normally 12 pairs of ribs. The first seven pairs are attached directly to the sternum by costal cartilages and are called true ribs. The 8th, 9th, and 10th pairs-false ribs-do not join the sternum directly but are connected to the 7th rib by cartilage.

Detailed explanation-2: -The upper seven pairs of ribs are known as true ribs because their costal cartilages articulate anteriorly directly with the sternum. The lower five pairs of ribs (ribs eight to twelve) are known as false ribs because their costal cartilages do not articulate directly with the sternum.

Detailed explanation-3: -The first seven sets of ribs are called true ribs. Costal cartilage anchors them to the edge of the sternum, or breastbone, in the middle of the chest at the front of the body. These ribs attach to the thoracic vertebra of the spinal column in the back. Ribs 8–10 are known as false ribs.

Detailed explanation-4: -According to their attachment to the sternum, the ribs are classified into three groups: true, false, and floating ribs. The true ribs are the ribs that directly articulate with the sternum with their costal cartilages; they are the first seven ribs.