Chapter 3 HW Flashcards
Functions of Nerve cell endings in the dermis
Nerve endings serve as receptors, they include warm receptors, cold receptors, pain receptors, and pressure receptors, they can also detect movement.
Signs of a first degree burn
Most common of burns, sunburns are often first-degree. Involves only the epidermis and includes redness, pain, swelling, and blisters
Signs of a second degree burn
Redness, pain, swelling, and blisters
Sometimes called partial thickness burns, involve the epidermis and dermis.
Stratum Lucidum
Found only in thick skin
Fibroblasts
Located in the Dermis and produces the two protein fibers collagen and elastic
How do vitamin A and C contribute to healthy skin
They are necessary for collagen production
How does the process of sweating help the body regulate temperature
Sweat produced on the skin will evaporate and cool the body if body temp is too high
Melanocytes
Reside in the stratum basale (deepest layer of epidermis). Responsible for the skin’s pigment.
The skins consists of which two layers
Epidermis and dermis
Arrangement of what feature in the dermis creates unique fingerprints?
Papillae: bumps on the superficial edge of the dermis, which are in direct contact with the epidermis
Keratinocytes
Their purpose is to grow and divide. They produce and fill themselves with keratin (a hard, waterproof protein), making the skin waterproof. This allows water retention in the body.
Skin is what percentage of body weight?
About 15%
Stratum basale
It dips into the dermis of the skin to form the hair follicles, is the deepest layer of the epidermis, and contains a single layer of cuboidal cells. It’s the only stratum of the epi with cells that actively grow and divide to produce new epidermis.
Layers and cell direction in the epidermis
Stratum basale > Stratum spinosum > Stratum granulosum > Stratum lucidum > Stratum corneum
Epidermis cell type responsible for skin pigment
Melanocytes (produce skin pigments called melanin)
What is the body’s largest organ
Skin
Elasticity
Allows skin to come back to shape if stretched
What’s the difference between thick and thin skin?
The presence of Stratum lucidum is only in thick skin. It is found on the lips, palms of the hands, and on the plantar surface of the feet. Thick skin has no hair, while thin skin does.
Function of collagen fibers in skin
Give the skin strength
Function of dendritic cells in the skin
Alert the body’s immune system to the invasion of pathogens (disease causing foreign invaders) that could make it through the stratum corneum
Nail matrix
(The nail’s growth center) at the root of the nail is composed of active keratinocytes in the stratum basale
What is cornification?
The process of epidermal cells filling with keratin and moving to the surface of the epidermis to form a durable waterproof layer
Hypodermis (subcutaneous layer)
It is not a layer of skin. It lies deep to the dermis, is mainly composed of adipose tissue, and connects the skin to the body
Dermis
Composed of loose/areolar connective tissue over dense irregular connective tissue. The dermis is the skins deepest layer. Has cutaneous glands, hair follicles, nerve endings, fibers, and blood vessels.
The Rule of Nines
Is how you determine the extent of a burn in relation to the body’s surface area.
The body is divided into 11 areas, each with 9% of the body’s surface area, 1% for the genital area.
Sebum
A very oily, lipid-rich substance produced by the sebaceous gland to moisturize the skin and hair
Tactile corpuscles
Allows skin to feel fine touch
Sebaceous gland
Produces sebum and its gland duct leads to the hair follicle surrounding the hair root
Terminal hair
Thick, coarse, and heavily pigmented, forms the eyebrows, eyelashes, and hair on the scalp
Lanugo hair
Very fine, unpigmented (colorless), forms on a fetus during the last three months of its development
Signs of third degree burn
Full thickness burns, most serious. Symptoms are charring and no pain. No hair follicles.
What type of epidermal cells composes the eponychium of the nail?
Eponychium (also known as the cuticle), is composed of stratum corneum cells extending onto the nail bed
Epidermis
Skin’s most superficial layer, composed of stratified squamous epithelial tissue.
Hair Shaft
Section of the hair extending out from the skin’s surface
How does skin protect the body?
Dead, cornified stratum corneum of the skin makes entry for bacteria difficult. Skin’s surface is dry, with an acidic pH making it a unfriendly place for bacteria to grow. Dendritic cells of the epidermis stand guard against pathogens trying to make it past the stratum corneum.
Why is Vitamin D production by the skin important to the body?
Vitamin D is important for the absorption of calcium from the diet into the bloodstream. It is important for homeostasis.
Effects of Aging skin
Loss of some of the sebaceous and sweat glands in the dermis. Dermis thins and the number of collagen and elastic fibers is reduced causing saggy and wrinkly skin. Blood vessels become more fragile and respond less quickly to temperature regulation
Effects of aging hair
Terminal hairs become coarser, loss of hair follicle melanocytes causes hair to go gray, hair on scalp becomes thinner, it also becomes drier as there is a reduced number of sebaceous glands
Eponychium (cuticle)
At the proximal edge of the nail body, is composed of stratum corneum cells extending onto the nail bed
