Unit 321: Apply microdermabrasion
The dermis and appendages
The subcutaneous layer
Functions of the skin
Where is the dermis located?
It is located beneath the epidermis and above the
It is the largest layer, and varies from 1.5 mm to 4 mm in
What are the functions of the dermis?
The main functions of the dermis are to regulate temperature, and to
protect, support and nourish the skin.
Much of the bodys water supply is stored within the dermis
What is the structure of the dermis?
It is composed of two layers of areolar connective tissue and contains:
Sensory receptors/nerve endings
- Eccrine: found all over the body
- Apocrine: found in the groin and axillae
Hair follicles/hair shaft/hair bulb
Arrector pili muscle
Blood and lymphatic vessels
The dermis consists of two layers:
1. 1. The papillary layer
2. 2. The reticular layer
The papillary layer
The upper, papillary layer, contains small cone–
shaped projections called papillae, which contain
looped blood capillaries carrying blood and lymph.
There are also tactile corpuscles and nerve
The papillary layer supplies nutrients to the
epidermis and regulates temperature.
The reticular layer
The lower, reticular layer, is thicker and contains fibroblast cells, which
are responsible for the formation of collagen fibres and elastin.
Yellow elastin fibres give the skin its flexibility and elasticity.
White collagen fibres plump the skin and give strength and firmness.
Specialised cells are also found in the reticular layer:
Macrophages destroy bacteria and tissue debris
Mast cells secrete histamine, which causes vasodilation, and
heparin, which stops blood clotting (anti-coagulant).
The reticular layer supports other components of the skin, such as hair
follicles, sweat glands, and sebaceous glands.
Nerve endings of the dermis
Meissner's corpuscles are for light touch and lie immediately
beneath the basement membrane of the epidermis
Pacinian corpuscles are for deep pressure, and lie deeper in the
Free nerve endings are for pain and temperature, and these
endings lie at the superficial aspect of the dermis
Subcutaneous layer (hypodermis)
The deepest layer lying directly above the muscles of the body and
below the dermis of the skin.
It is made up of two main types of connective tissue:
Adipose tissue forms a network of fat cells providing the body
with insulation, as well as acting as a source of energy
Areolar tissue gives strength to protect underlying structures.
Elasticity to cope with increases in size, and support for blood
vessels and nerve endings found in this layer
Label the cross section diagram of the skin
Blood & Lymph
Functions of the skin
• HEAT REGULATION
• NUTRITION – Production of Vitamin D