Final answer:
Long bones are characterized by a central shaft called the diaphysis and rounded ends called epiphyses. They function as levers in the body, are essential in movement, support, protection, mineral storage, and blood cell production. Examples include the femur, tibia, ulna, radius, metacarpals and phalanges.
Step-by-step explanation:
Long Bones: Features and Functions
Long bones are characterized by being longer than they are wide, typically having a cylindrical shape. They are composed of a central shaft known as the diaphysis which contains bone marrow within a marrow cavity. The ends of long bones are called the epiphyses, which are rounded and covered with articular cartilage. Spongy bone within the epiphysis contains red marrow, vital for the production of blood cells. An integral part of the musculoskeletal system, these bones function primarily as levers, moving when muscles contract.
The limbs of the human body primarily consist of long bones such as the femur, tibia, ulna, and radius. Long bones facilitate body movement, protect internal organs, support body structure, and help in the storage of minerals and fat, an essential process known as hematopoiesis. In growing bones, long bones feature the epiphyseal plate (growth plate) located in the metaphysis. Once growth ceases in early adulthood, this plate becomes an epiphyseal line evidencing former growth regions.
Examples of long bones include the humerus, ulna, radius, femur, tibia, fibula, metacarpals, and phalanges. These examples show that while the term 'long bone' refers to the shape, it is not indicative of size, as even the smaller bones in the fingers (phalanges) and toes (metatarsals) are classified as long bones due to their shape and structure.