General Anatomy Lecture 2 Skin & Fascia PDF

B a l a g ra e U n i ve rs i t y Fa c u l t y o f D e nt i st r y GENERAL ANATOMY DR. Bubaker Elwerfalli Consultant of urologic surgery, MD Msc in Anatomy  Lecture 2 Skin & Fascia  Objectives...

B a l a g ra e U n i ve rs i t y Fa c u l t y o f D e nt i st r y GENERAL ANATOMY DR. Bubaker Elwerfalli Consultant of urologic surgery, MD Msc in Anatomy  Lecture 2 Skin & Fascia  Objectives 1. Describe layers of skin. 2. Enlist the functions of skin. 3. Define appendages of skin. 4. Define Fascia. 5. Differentiate between Superficial and deep fascia  SKIN Considered as : largest organ of the body with a surface area about 2 m². Divided into: 1. Superficial part : epidermis. 2. Deep part : dermis.  Skin anatomy Skin consists of two regions: 1. Epidermis 2. Dermis Epidermis ‫البشرة‬:  It is made up of stratified squamous keratinized epithelium. Epidermis ‫البشرة‬:  it is thick in some areas as in palms of hands and soles of feet.  it is thin in some areas as anterior surface of arm and forearm.. 2. Dermis ‫ اآلدمة‬. deep layer which is made up of connective tissue (collagen and elastic fibers), It contains nerves, blood vessels. Skin Appendages 1. Nails. 2. Hair Follicles. 3. Sebaceous Glands. 4. Sweat Glands.  Nails  Keratinized plates on dorsal surfaces of tips of fingers and toes.  Its formed of root, body and free border  Related Structures : Root of nail : proximal edge of plate. Nail folds : skin folds surrounding the nail. Nail bed : the surface of the skin covered by the nail. A hair follicle A hair follicle is a tube- like structure (pore) that surrounds the root and strand of a hair SEBACEOUS GLANDS Produces sebum, Their duct open in the hair follicles Sebum is an oily substance  that protects skin from drying out.  Prevents excessive water loss from the skin  Inhibits the growth of certain bacteria Sweat Glands They produce sweat. There are about 2-4 million glands throughout the body Functions of skin: 1.Protection of internal structures. 2.Secretion of sweat which helps in regulation of body temperature. 3.Sensation e.g touch, pain and temperature. 4.A barrier against fluid loss, bacteria, viruses  Fascia  It is the connective tissue that lies between the skin and the underlying muscles and bones.  It is divided into, superficial & deep layers.  Fascia Superficial fascia: – It is found immediately under the skin. – It consists of connective tissue. – It contains a variable amount of fat, blood vessels and nerves of the skin. – It is extremely thin or absent in the eyelids, external ear.  Fascia Function : 1) Its fat content keeps the body temperature and give the body a rounded contour especially in females. 2) It allows free mobility of the skin.  It is a dense, connective tissue lies deep to superficial fascia. It covers most of the body. However, it absent in certain regions e.g. in the face, and abdomen.  It covers the muscles and other deep structures.  In the limbs it forms a sheath around the muscles.