Anatomy & Physiology of the Skin
The skin is a highly underestimated organ. It performs many vital functions and has a complex structure which most people are unaware of. This page provides a basic overview of the anatomy and physiology (structure and function) of the human skin.
It is hoped that the reader will gain a deeper understanding and respect for their skin and understand why it is so important to take care of the skin and maintain its health through the use of a regular skin care regime.
Basic Anatomy & Physiology of the Skin
The skin is an organ because it consists of different tissues that are joined to perform specific activities. It is one of the largest organs of the body in surface area and weight. In adults, the skin covers an area of about 2 square meters, and weighs 4.5 to 5 kg. It ranges in thickness from 0.5 to 4.0 mm, depending on location. The skin is not just a simple, thin coat that keeps the body together and provides protection. It performs several essential functions. Dermatology (der'-ma-TOL-o-je; dermado = skin; logos = study of) is the medical specialty that deals with diagnosing and treating skin disorders.
Anatomy of the Skin
Structurally, the skin consists of two principal parts. The outer, thinner portion, which is composed of epithelium, is called the epidermis. The epidermis is attached to the inner, thicker, connective tissue part called the dermis. Beneath the dermis is a subcutaneous (subQ)
Physiology of the Skin
Skin serves several functions, which are introduced here.
Regulation of body temperature.
In response to high environmental temperature or strenuous exercise, the evaporation of sweat from the skin surface helps lower an elevated body temperature to normal. In response to low environmental temperature, production of sweat is decreased, which helps conserve heat. Changes in the flow of blood to the skin also help regulate body temperature.
The skin covers the body and provides a physical barrier that protects underlying tissues from physical abrasion, bacterial invasion, dehydration, and ultraviolet (UV) radiation. Hair and nails also have protective functions.
The skin contains abundant nerve endings and receptors that detect stimuli related to temperature, touch, pressure, and pain.
Besides removing heat and some water from the body, sweat also is the vehicle for excretion of a small amount of salts and several organic compounds.
Certain cells of the epidermis are important components of the immune system, which fends off foreign invaders.
The dermis of the skin houses extensive networks of blood vessels that carry 8 to 10% of the total blood flow in a resting adult. In moderate exercise, skin blood flow may increase, which helps dissipate heat from the body. During hard exercise, however, skin blood vessels constrict (narrow) somewhat, and more blood is able to circulate to contracting muscles.
Synthesis of Vitamin D.
Vitamin D is a group of closely related compounds. Synthesis of vitamin D begins with activation of a precursor molecule in the skin by ultraviolet (UV) rays in sunlight. Enzymes in the liver and kidneys then modify the molecule, finally producing calcitriol, the most active form of vitamin D. Calcitriol contributes to the homeostasis of body fluids by aiding absorption of calcium in foods. According to the synthesis sequence just described, vitamin D is a hormone, since it is produced in one location in the body, transported by the blood, and then exerts its effect in another location. In this respect, the skin may be considered an endocrine organ.
Part II: Epidermis & Dermis of the skin
Find more inforamtion on this topic:
Natural Skin Care Newsletter
- - -
All our skin care products have been developed primarily to help our patients with a wide range of skin care problems for the past 30 years.
Susan and Danny practice Western herbal medicine, Acupuncture, Chinese herbal medicine, Remedial body therapies at their private practice in the lower Blue Mountains, West of Sydney.
Their combined experience in treating skin and other disorders is well over 50 years and they're happy to help you regain your optimal health.
- - -
- - -
WILDCRAFTED HERBAL PRODUCTS™
ABN 97 131 307 643
Wildcrafted's Natural Skin Care Products are Your Natural Skin Care Solution
© Copyright: 2004 - 2013, Wildcrafted Herbal Products Pty Ltd. All rights reserved worldwide