Organ Systems – Integumentary System
The Human body is made up of eleven distinctive organ systems. Each organ system play specific roles in the functions of the body. The integumentary system acts as a protective cover for the human body.
The Integumentary system
The integumentary system is composed of hair, skin and nails. The skin is the main component of the Integumentary system, hair and nails are an accessory component. This system consists of three layers: Epidermis (outermost layer) dermis (middle layer) hypodermis (bottom layer). The Epidermis contains melanocytes, melanocytes are cells that produce melanin. Melanin is the dark pigment that gives skin its color. Langerhans, immune cells and nerve cells make up the epidermal layer. The epidermis does not contain blood vessels. Keratinocytes make up of ninety-five percent of the epidermal layer it provides strength and flexibility. Keratinocytes are produced through mitosis and move up the layers to the top which take up to five weeks. The Epidermis has five distinctive layers: the Stratum corneum (the horny layer of the skin), The Stratum luicidum (which is located in the hands and feet), the stratum granulosum (the thin layer of the epidermis), Stratum spinosum (spinney like middle layer) and Stratum Basale (The deepest layer of the epidermis). Connective tissues are found in the dermis as they provide strength and elasticity through collagen and elastin. The Dermis contains blood vessels, nerve receptors, immune cells, glands and hair roots. The glands are multi-cellular structures that are specialized for the secretion storage and structure of chemical substances. The Merocrine (sweat glands) and Apocrine (sebaceous glands) are two variations of the glands. The Merocrine gland is widely distributed through the body. Sweat is filtered into a duct and released onto the skin’s surface. The Apocrine gland less common in the armpits, around nipples and in the groin and are connected to hair follicles and interact with bacteria to cause body odor. The final layer of the skin is the dermis which contains connective tissue and fatty tissue, nerves and blood vessels.