Final answer:
The folds of the skin on either side of the nail groove are called the nail fold. These folds overlap and hold the nail body in place. The nail bed is a specialized structure of the epidermis that the nail body is formed on.
Step-by-step explanation:
The folds of the skin on either side of the nail groove are called the nail fold. These folds of epithelium overlap and hold the nail body in place. The nail fold that meets the proximal end of the nail body forms the nail cuticle, also known as the eponychium. The nail bed is a specialized structure of the epidermis that the nail body is formed on, and it is rich in blood vessels, giving it a pink appearance.