Final answer:
Cartilage is the flexible connective tissue in the skeleton that is not as hard as bone and allows for smoother movement at joints. It lacks the high calcium content that gives bones their rigidity. Found in areas that require flexibility like the ribcage and joints, cartilage is crucial for efficient and pain-free movement.
Step-by-step explanation:
The part of the bone that is a strong tissue, not as hard as bone, but is more flexible, is called cartilage. Cartilage is a type of dense connective tissue composed of tough protein fibers that is strong yet flexible and very smooth. It is found in the skeletal system, including areas like the ends of bones at joints, providing a smooth surface for bones to move over.
In comparison to bone, or osseous tissue, cartilage does not contain as much calcium, which is what makes bones rigid. The flexibility of cartilage is crucial for certain parts of the body where movement is necessary, such as the ribcage and joints. Unlike bone tissue, which is highly vascularized and can recover from injuries rapidly, cartilage lacks this vascularization, which can lead to slower healing when damaged.