Skin Structure And Growth Flashcards
What % of the skin is water?
50%-70%
Epidermis
The outermost and thinnest layer of the skin. It’s contains no blood vessels.
Stratum Corneum
also known as the horny layer, epidermis’ outer layer and is what we see when we look at the skin. It has overlapping skin cells and forms a barrier to protect underlying tissues from infection, dehydration, chemicals, and mechanical stress.
Keratin
fibrous protein that is also the principal component of skin, hair, and nails.
Barrier function
complex of lipids that keep the skin moist by preventing water evaporation and guards against irritants penetrating the skin surface; and to help regulate the skin’s pH
Stratum Lucidum
the clear, translucent layer under the stratum corneum; it consists of small cells through which light can pass. This layer is located only on the palms of the hands, soles of the feet, and digits.
Stratum Granulosum
also known as the granular layer, is the layer of the epidermis composed of cells that look like granules and are filled with keratin. The cells die as they are pushed to the surface to replace dead cells shed from the stratum corneum.
Stratum Spinosum
also known as the spiny layer, is just above the stratum germinativum. The spiny layer is where the process of skin cell shedding begins. The spinosum is the largest layer of the epidermis.
Stratum Germinativum
basal cell layer is the epidermis’ deepest layer. This is the living layer where everything starts or germinates! This layer produces new epidermal skin cells and is responsible for the growth of the epidermis. It is composed of several layers. The basal cell layer also contains melanin cells.
Dermis
AKA: derma, corium, cutis, or true skin, is the underlying or inner layer. The dermis extends to form the subcutaneous tissue. The highly sensitive dermis layer of connective tissue is about 25 times thicker than the epidermis.
The Papillary Layer
The dermis’ outer layer, directly below the epidermis
Dermal Papillae
membranes of ridges and grooves that attach to the epidermis. Some papillae contain looped capillaries, and others contain small epidermal structures called tactile corpuscles , with nerve endings that are sensitive to touch, pain, heat, cold, and pressure
Tactile Corpuscles
small epidermal structures with nerve endings that are sensitive to touch and pressure
Hair papillae
cone-shaped elevations at the base of the follicle that fit into the hair bulb; papillae are filled with tissue that contains the blood vessels and cells necessary for hair growth and follicle nourishment
dermal/epidermal junction (DEJ)
top of the papillary layer where it joins the epidermis