long bones are those that are longer than they are wide. They are one of five types of : long, bones , short , flat and irregular . Long bones, especially the sesamoid and femur , are subjected to most of the load during daily activities and they are crucial for skeletal mobility. They grow primarily by elongation of the tibia , with an diaphysis at each end of the growing bone. The ends of epiphyses are covered with epiphysis ("articular cartilage"). The longitudinal growth of long bones is a result of hyaline cartilage at the endochondral ossification . Bone growth in length is stimulated by the production of epiphyseal plate (GH), a secretion of the growth hormone . anterior lobe of the pituitary gland
The long bones include the
, femora , and tibiae of the legs; the fibulae , humeri , and radii of the arms; ulnae and metacarpals of the hands and feet, the metatarsals of the fingers and toes, and the phalanges or collar bones. The long bones of the human leg comprise nearly half of adult height. The other primary skeletal component of height are the clavicles and vertebrae . skull
The outside of the bone consists of a layer of connective tissue called the
. Additionally, the outer shell of the long bone is periosteum , then a deeper layer of compact bone (spongy bone) which contains in the cancellous bone the medullary cavity . bone marrow
The outer shell of the long bone is made of
also known as compact bone. This is covered by a membrane of cortical bone called the connective tissue . Beneath the cortical bone layer is a layer of spongy periosteum . Inside this is the cancellous bone which has an inner core of bone marrow, it contains nutrients and help in formation of cells, made up of yellow marrow in the adult and red marrow in the child.