Wednesday, September 08, 2010

Healthy Skin Naturally: Skin Structure, the epidermis

Welcome to the first section of my discussion on Ms. Tourles' book, Naturally Healthy Skin. As mentioned previously, I've divided my discussion of this chapter into three sections. For me, learning happens faster if I digest smaller bits at a time. It's important that I learn the new terminologies and their functions.

Skin structure, the epidermis

Skin structure varies in thickness depending on its function. Skin is thickest on our feet and hands. After all, our feet and hands are the two body parts that we use most to sense our world. On the other hand, our thinnest skin is our eye lids. Our eyes are our very delicate; they would need a soft layer to protect them.
Skin is a complex organ because its functions are so varied. It protects us internally as well as externally. Within one square inch of our skin’s surface, our skin contains hair, sebaceous glands, nerves, blood vessels, sweat glands, cells, nerve endings, sensory cells, temperature sensing apparatuses.

Our skin is made up of three layers: epidermal, dermal, and subcutaneous. Within each of these layers are additional layers.

The epidermis contains five layers:
  1. Stratum corneum is our outermost layer of skin composed of large, plate-like envelopes filled with keratin, which are dead cells that have migrated up from the stratum granulosum; this layer protects us from environmental elements and helps keep our skin hydrated by preventing water evaporation.
  2. Stratum lucidum is found throughout the body but is thickest in the soles of our feet and in the palms of our hands; it is composed of between three to five layers of keratinocytes, (forms the keratin layer that protects the skin and underlying tissue from environmental damage such as heat, UV radiation and water loss).
  3. Stratum granulosum (or granular layer) keratinocytes are called granules that contain keratohyalin (a protein that may promote aggregation and cross-linking of the keratin fibers).
  4. Stratum spinosum also called ‘prickle-cell’ due to its spiny appearance creates a hydrophobic barrier that prevents dehydration.
  5. Stratum basale, the deepest layer of the epidermis, is a continuous layer of cells, considered the stem cells of the epidermis, are proliferate and create ‘daughter’ cells that migrate
The photograph below shows the different layers.

http://en.wikipedia.org/wiki/File:Skinlayers.png



















____________________________________
Skin structure, its dermis and subcutaneous will be in my next blog.

No comments: