The branch of anatomy that studies the large parts of the human body is called regional anatomy. Regional anatomy is a subdivision of gross anatomy, which is the study of large structures that can be seen with the naked eye. Regional anatomy focuses on specific internal or external body regions and how different parts interact and cooperate in that region. For example, the body can be divided into regions such as the upper limb, lower limb, trunk, thorax, abdomen, pelvis, head, and neck. Each region contains its respective bones, joints, muscles, arteries, veins, nerves, lymphatics, and organs.