What is Skin-basic structure and function

What is Skin-basic structure and function :- Skin is the largest organ of the body it is a protective covering from the skeletal system and vital organs. It contain many special structure including follicles, hair, nails, sweet gland and sebaceous. Skin is the elastic and at the surface is a dead substance with a constantly being shed and replaced by a new growth. Our skin is composed of a protein known as keratin. Hair is also composed of this substance.

Structure and function of skin

What is Skin basic structure and function
What is Skin basic structure and function

The skin form the external covering of the body and it is largest organ constituting 15- 20% of its total mass. The skin may be three types of basic layers

  1. Epidermis
  2. Dermis
  3. Hypo-dermis


Epidermis is composed of keratinized stratified epithelium and is derived from the ectoderm. The epidermis is the outer of top layer and is made up of five sub-layers.

  1. Stratum Corneum
  2. Stratum Lucidium
  3. Stratum granulosum
  4. Stratum Basall
  5. Stratum spinous

Stratum Corneum

The upper most layer is stratum corneum which is composed of keratinized cells called corneum. The cell in the stratum corneum are the most differentiated cell in the skin.

Stratum lucidium

Stratum lucidum is sometimes observed as the fifth layer. The stratum lucidium layers is only found on the palm of your hands and soles of your feet. This is layer that thickness and fight mechanical attacks.

Stratum Granulosum

The stratum granulosum which contain numerous intensely staining granules. This is the most superficial layer of the non keratinized portion of the epidermis. The sell contained numerous keratinized  granules hence the name of the layers. This layer varies from 1-3 cells thick.

Stratum Spinous

The Third layer is termed at the stratum spinous because of the characteristic light microscopic appearance of short process extending from Cell to cell it is also called the Spanish or prickle cell layer.

Stratum basal

Stratum basal is the fourth layer and the father most layer of the epidermis is the stratum basal. It is represented by a single layer of cells that rest on the basal lamina. It is also termed as the stratum germinativum.


Basic and very important part of the skin is the dermis. It is composed of connective tissue containing collagen and elastic fibres . The term is very thick and Palm and sole are very thin areas such as a eyelids and scrotum. The superficial portion of the dermis is termed the Papillary layer. It  consists of areolar connective tissue containing fine elastic fibres.

The deeper and inner portion of the dermis is called the reticular layer. It consists of dense irregular connective tissue containing interlacing bundles of collagen and some coarse if plastic fibres.


The Reticular reasons is attached to underlying organ such as bone and muscles by the subcutaneous layer called the hypo dermis  or superficial fascia.

Function of skin


physical absorption bacteria invasion dehydration and UV. Hair and nails also have product functions.


The skin contain abundant nerve ending and receptors that detect stimuli related to temperature touch pressure and pain.

Regulation of body temperature

The skin help regulate the body temperature by means of perspiration.


Besides removing heat and some water from the body sweet also is the vehicles for loss of a small quantity of ion and several organic. compound


It provide immunologic information obtained during antigen processing to the appropriate effect of cell in the lymphatic tissue.

Endocrine function

Skin is also considering and endocrine organ as it secretes hormones, cytokines and growth factors and converts precursor molecule into hormonally active molecules (Vitamin D)

Blood Reservoir

Drug Delivery Route