L11 Gross anatomy of skin and fascia Flashcards
what is skin?
-the largest organ in the body
-made up of superficial epithelium ( epidermis & dermis )
Dermis
-the deep CT layer of skin
-contains nerve terminals, collagen & elastic fibers
What do collagen fibers do?
Determines the tension and wrinkle lines in the skin
What are tension lines?
Lines in the skin that run :
-longitudinally in limbs
-transversely in the neck and trunk
What do elastic fibers do?
Fibers in the dermis that deteriorate with age, leading to wrinkles and sagging of the skin bcs it loses its elasticity
What are arterioles involved in?
Involved in the loss or retention of body heat
-dilate to fill superficial capillary beds to radiate heat
What is vascular supply?
Arteries supplying the dermis:
-derived from branches of arteries supplying skeletal muscle
-supply directly to the skin
How do stretch marks form?
White marks formed in the dermis due to damage of collagen fiber from stretching, commonly seen in pregnancy ( striae gravidarum )
What does surgical incision cause?
An incision made along tension lines causes minimum disruption of collagen so that the wound heals with a small scar
What is tattooing?
A permanent coloration of the skin by depositing a foreign pigment into the dermis with a needle
What are nails?
Plates of keratinized epidermal cells that form a clear solid covering over the dorsal surfaces of the distal portions of the digits
Functions of nails:
-protect distal ends of the digits
-provide support and enhance touch perception
-allow to grasp objects and scratch our body
What are the severity of burns?
First degree burns
-only epidermis is damaged
-skin is red and swollen
Second degree burns
-epidermis & superficial dermis damaged
-skin is red with blisters
Third degree burns
-entire thickness of skin is damaged
-burn is gray white or black
What is skin graft?
Transferring of tissue from one site to another, used when skin is damaged
Methods of skin grafting:
Split thickness grafting: transfer epidermis only
Full thickness grafting: transfer both epidermis and dermis