Integument

The integument is defined as the outermost covering of an organism, which includes the skin, the appendages of the skin (such as hair, nails, skin glands), the subcutaneous tissue, the breast and the scalp.

The integument serves multiple functions, including providing a physical barrier, facilitating immunological surveillance, and performing sensory, thermoregulatory, and biosynthetic roles.

Histologically, the integument consists of two main layers: the epidermis and the dermis, with a subcutaneous layer called the hypodermis lying beneath the dermis. The epidermis is primarily composed of keratinocytes and includes several layers, while the dermis contains connective tissue, blood vessels, and various glands. The integument's structure and function can vary significantly across different species, reflecting adaptations to their specific environments