Structure of the skin - Lash Lift

Structure of the Skin

5 Fun Facts

I think so anyway...

The Epidermis

The epidermis is the most superficial layer of the skin, which varies in thickness in different parts of the body, the thickest on the palms of the hands and soles of the feet.

There are no blood vessels or nerve endings in the epidermis, but its deeper layers are bathed in fluid from the dermis, which provides oxygen and nutrients, and is drained away as lymph.

There are several layers of cells in the epidermis which extend from the deepest Germinative layer to the surface Corneum (a thick horny layer).

The cells on the surface are flat, thin, non-nucleated, dead cells, in which the cytoplasm has been replaced by the fibrous protein keratin.

These cells are constantly being rubbed off and replaced by cells, which originated in the Germinative layer and have undergone gradual change as they progress towards the surface.

Complete replacement of the epidermis takes between 21-55 days.e are they and what are their movements.

The main layers of the epidermis:

Corneum (horny layer)

Lucidum (clear layer)

Granulosum (granular layer)

Spinosum (prickle layer)

Germinativum (basal layer)

The Dermis

The dermis is tough and elastic. It is formed from connective tissue and the matrix contains collagen fibres interlaced with elastic fibres.

It is the dermis where collagen is stimulated and products used need to penetrate into the dermis, stimulating the renewal of skin cells.

Collagen fibres bind water and give the skin its strength, but as its ability declines with age, wrinkles develop.

Many products work on the surface and we need products with molecules small enough to penetrate into the dermis.

Rupture of elastic fibres occurs when the skin is overstretched, resulting in the permanent striae, or stretch marks, that may be found in obesity and pregnancy.

The structures in the dermis are:

- Blood vessels- Lymph vessels (for drainage of excess fluids) - Sensory nerve endings - Sweat glands and their ducts - Hairs, arrector pili muscles and sebaceous glands

Blood vessels

A network of capillary branches which supplies and transports blood cells, nutrients, and oxygen to the tissues of the body, including sweat glands, sebaceous glands, hair follicles and the dermis.

The epidermis has no blood supply. It obtains nutrients and oxygen from interstitial fluid derived from the papillae of the dermis.

Sensory nerve endings

Sensory receptors, which are sensitive to touch, temperature, pressure and pain are widely distributed in the dermis.

The skin is an important sensory organ through which individuals receive information about their environment.

Nerve impulses generated in the sensory receptors in the dermis are conveyed to the spinal cord, then to the sensory area of the cerebrum where sensations are perceived.

Sweat glands

Sweat glands are found widely distributed throughout the skin and are numerous in the palms of the hands, soles of the feet, axillae and groins.

The bodies of the glands lie coiled in the subcutaneous layer. Some ducts open onto the skin surface through pores, and others open into hair follicles.

Ducts opening into hair follicles do not become active until puberty. The most important function of sweat glands is to regulate body temperature.

Subcutaneous Layer

The Subcutaneous Layer is also called the hypodermis and it attaches to underlying tissues and organs. It is the layer of tissue that is directly beneath the skin.

It contains blood vessels and nerves to transit to the more superficial layers of the skinIt also contains lemellated (pacinian) corpuscles that detect external pressure applied to the skin

It also contains lemellated (pacinian) corpuscles that detect external pressure applied to the skin

Subcutaneous tissue consist mainly of fat and it acts as an insulator for the body.

It may vary from very minimal, such as in areas of the eyelids, or as a thick layer as in the fat padding around the abdomen and waist.

The subcutaneous layer is mainly composed of loose fibrous connective tissue and fat (adipose) cells interlaced with blood vessels. The hypodermis (subcutaneous layer) is generally about 8% thicker in females than in males.

The main functions of the hypodermis are insulation, storage of lipids, cushioning of the body and temperature regulation.