Final answer:
A curved portion of a bone is typically characterized as a 'flat bone,' which, despite its name, is often curved. Flat bones include the scapula and ribs, providing attachment points and protecting internal organs.
Step-by-step explanation:
The curved portion of a bone is often referred to as a flat bone. Flat bones are typically thin and curved structures in the body that serve as points of attachment for muscles and often protect internal organs. An example of a flat bone is the scapula or shoulder blade. These are not to be confused with irregular bones, which have complex shapes and include bones such as vertebrae and some skull bones, or with long bones that have a shaft and two ends, like the femur.
Bone markings can be classified into three groups: articulations, projections, and holes. A projection is a part of the surface that sticks out above the rest, providing attachment points for tendons and ligaments. However, it does not serve as a definition for a curved portion of the bone. Therefore, while projections are essential features, they are distinct from the curvature characterizing flat bones.