The Integumentary (skin) system consists of: -
- Epidermal layer
- Dermal layer
- Sudoriferous and Sebaceous glands
- Hair and Nails
The Epidermal Layer: is the thin outer layer that has an important element, melanin which is responsible for giving skin its color and protects the skin from ultra-violet rays and also allows tan to the skin. This layer also includes the protein keratin, which stiffens epidermal tissue to form nails.
Dermal Layer: the bottom-most inner layer of skin known as dermal layer or Dermis is comprised of the blood vessels, connective tissue, nerves, lymph vessels, sweat glands and hair shafts. The female gets its characteristic curves due to the fat distribution in this layer.
Sudoriferous and Sebaceous glands: -
Sudoriferous glands are none other than sweat glands. These glands have eccrine glands, which are deep in the skin that connect to the surface. They secrete sweat. The apocrine glands are in armpits, areolae of nipples, and the genital region. They contain pheromones and secrete such substances leads to sexual arousal.
Sebaceous glands: -- are oil glands that are present all over the body except the soles of feet and palms of hand. The sebum in the sebaceous gland keeps the hair moist and prevents the skin from drying.
Hair and Nails: - Hair is nothing but cornified thread, which is developed from the epidermis. The hair covers most of the body. It protects the various body parts like eyebrows prevent the sweat from entering into the eyes, ears and nose. Hair filter dust from air and the hair on the scalp protects it from the harsh sunrays and abrasions. Hair has a protective function: eyebrows keep sweat from running into the eyes, nose and ear hairs filter dust from the air, and scalp hairs protect against abrasion and overexposure to sun rays. Nails:- Similar to hair, nails are developed from the epidermis. They are hard plates of keratinized cells and are at the ends of fingers and toes. The Nails appear pink due to their translucency, which reveals the vascular tissue beneath. They help in grasping objects, scratching, and protecting fingers and toes.