Question

Name the bone which is not attached to any other bone in the human body.
A. Hyoid
B. Femur
C. Sacrum
D. Tarsus

Answer 1

Hint: Many bones together form a skeletal system. A bone meets another bone at the bone-joints. One U-shaped bone exists in humans which is not linked to any other bone.

Complete answer: The skeletal system consists of different types of bones. The bones provide a rigid structure, stability and protection. But what are bones? Bones are basically highly vascularized, calcified matrices. Collagen and calcium phosphate are the main constituents of bone. It has deposits of calcium salts and rich blood supply. At birth, human babies possess about 270-300 bones. As development proceeds, some bones get fused together to form larger bones. Adult human beings have nearly 206 bones. Two or more bones meet in certain regions, which are called joints. There are many types of joints including fixed and mobile joints viz. ball-socket joint, hinge joint, pivot joint etc.
But there is only one bone which is not joined with any other bone. It is the U-shaped bone found at the base of the buccal cavity. It is called the hyoid bone. Commonly it is known as lingual or tongue bone. The main function of it is to act as a tongue anchoring mechanism.
So, the correct option is A. Hyoid

Note: Bone cells are called osteocytes. These are of two types: osteoblasts and osteoclasts. The 206 bones have some long bones, some short, some sesamoid bones, flat and irregular bones. Though bone is mineralized tissue, it contains other types of tissues such as bone marrow, endosteum, periosteum and blood vessels.