Final answer:
The patella is the largest sesamoid bone in the body, helping to overcome compressive forces and increasing muscle leverage by articulating with the femur and elevating the tendon during knee joint movements.
Step-by-step explanation:
The patella, also known as the kneecap, is the largest sesamoid bone in the body. Sesamoid bones are distinctive due to their small, flat, and round shape, similar to a sesame seed, and their location within tendons which cross joints. The primary function of the patella is to protect tendons from compressive forces by helping them overcome these forces during joint movement, such as knee extension. The patella achieves this by articulating with the underlying bones, particularly the patellar surface of the femur, which prevents the tendon from rubbing against the bones during movement. Additionally, it increases the leverage of muscles by lifting the tendon away from the joint. Unlike the patella, which is found in every person, short bones are cuboidal in shape and can be found in regions such as the wrists and ankles. Flat bones, on the other hand, are typically thin, curved, and composed of two parallel layers of compact bone sandwiching a layer of spongy bone, with most skull bones and the sternum being examples of flat bones.