Femur is the largest and longest bone in human body. It forms the upper part of human leg. Its average length in adult male is 50.50 centimeter. This bone is also found in mammals, reptiles and vertebrates i.e frog, lizards, amphibians etc. Femur is Latin word which means thigh hence it is also known as thigh bone.
Tibia is the second largest bone in the human body and no doubt the strongest bone of human body because it bears the body weight of person. It forms the inner-lower part of human leg. The average length of tibia is 43.03 CM. Tibia is Latin word which means an ancient type of musical instrument. Shin bone and shank bone are other names of Tibia.
Fibula (also known as Calf Bone) is located in the outer-lower part of human leg. Fibula is the third largest bone in the human body. Fibula along with Tibia forms the lower part of human leg as it is located on the lateral side of Tibia. It is relatively weak and thin as compared with Tibia. The average length of tibia is 40.50 CM.
Humerus bone connects shoulder with elbow in human arm. It is a long bone which consists of three parts i.e. upper extremity of Humerus, body of Humerus and lower extremity of Humerus. Humerus forms the upper part of human arm and many important muscles are attached with it. The average length of tibia is 36.46 CM.
Ulna forms the inner-lower part of human arm. This fore-arm bone along with radius completes the lower part of human arm. Its average length in 28.20 Cm. In simple words it connects elbow with hand. It is a long and narrow bone with many muscles attached with it.