Chapter Six Flashcards
Epidermis
The outermost layer of the skin, consists of stratified squamous epithelial tissue
Dermis
The inner, deeper layer of the skin. Made of connective tissue. Contains primarily collagen fibers, but also has elastin fibers, and reticular fibers.
Papillae
Finger-like projections extend upward from the dermis.
Hypodermis
Subcutaneous tissue made of loose connective (areolar) tissue and adipose tissue.
Stratum Basale
basal layer
The innermost layer, consists of a layer of columnar stem cells
Stratum Germinativum
Other name for Stratum Basale
Keratin
Tough Fibrous protein
Stratum Corneum
Outermost layer
What is left of the dead cells is their keratin, which come and replace the dead cells that flake away with daily wear
Keratinocytes
newly flattened dead cells arriving from the inner laters of the epidermis
Langerhans Cells
Phagocytic Cells “pacman cells”
Merkel Cells
Sensory Receptors in the dermis
SQ
Subcutaneous Injection 45 degree insertion
ID
Intradermal Injection 15 degree insertion
Melanocytes
Cells that are scattered through the basal layer of the epidermis and produce a substance called melanin that accumulates in the cells of the epidermis
Melanin
Forms a cap over the top of the cells nucleus to protect it from harmful UV rays
What are the two types of Melanin?
Pheomelanin and Eumelanin
Pheomelanin
Reddish melanin
Eumelanin
Brown-Black melanin
Cyanosis
Skin Tone: Blue Tint
Cause: Deficiency of oxygen in circulating blood
Jaundice
Skin Tone: Yellow discoloration of skin and whites of eyes
Cause: Impaired liver function (ie. hepatitis or liver disease) that allows bile to accumulate which stains the skin
Bronzing
Skin Tone: Golden Brown skin color
Cause: Deficiency of hormones from the adrenal gland, such as occurs with Addison disease
Albinism
Skin Tone: Extremely pale skin, white hair, pink eyes
Cause: A genetic lack of melanin
Erythema
Skin Tone: Abnormal redness
Cause: Increased blood flow in dilated blood vessels close to the skins surface
Pallor
Skin Tone: Pale Skin
Cause: Decreased blood flow
Bruise (hematoma)
Skin Tone: Bluish, black, or yellow mark on skin
Cause: The breakdown of clotted blood under the skin
Functions of the skin:
Protection
Barrier
Vitamin D production
Sensory Perception
Thermoregulation
Encapsulated Nerve Endings
Pick up touch and pressure
Free Nerve Endings
Pick up heat, cold, pain, itch
Shaft
Part of the hair that extends above the skin’s surface
Hair Follicle
A sheath of epidermis that have rich nerve and blood supply
Bulb/Root
Lowest part of the hair, where the growth occurs
Papilla
Cluster of connective tissue and blood vessels that nourish each hair
Arrector Pili
Small bundle of smooth muscle, responsible for “making your hair stand on end”
Alopecia
Excessive hair loss
Male Pattern Baldness
Happens when a person has inherited a specific gene AND have high levels of testosterone which is why it typically occurs in men
Cuticle
A fold of skin that surrounds the nail body
Nail Body
Visible part of the nail
Lunula
Crescent-shaped white area at the base of the nail
Nail Bed
Layer of epithelium under the nail, appears pink because of rich blood supply in the area
Nail Root
Proximal end of the nail, hidden under overlying tissue
What are the two types of sweat glands?
Eccrine Gland and Apocrine Gland
Sebaceous Gland
Open into a hair follicle, secretes an oily substance called sebum to help keep the skin and hair from drying out and becoming brittle
Apocrine Gland
Contains a duct that leads to hair follicle
Located mainly in the axillary and anogenital regions
Are scent glands that respond to stress/sexual stimulation
Begin to function at puberty
Sweat produced here does not have strong over unless it collects on skin
Eccrine Gland
Contains duct that leads to skin surface
Widespread throughout the body but abundant on palms, forehead, and upper torso
Produce transparent watery fluid called sweat which contains potassium, ammonia, lactic acid, uric acid, and other waste
Sweat plays large role in helping body maintain a constant core temp
Ceruminous Glands
Glands that exist in the external ear canal.
Produce a waxy substance called Cerumen
Cerumen
Ear Wax
How many classifications of burns are there?
Three
First Degree Burns
- Involves only the epidermis
- Causes redness, slight swelling, and pain
- Often results from sunlight
Second Degree Burns
- Involves the epidermis as well as part of dermis
- results in blisters, severe pain, swelling
- may result with scarring
- may appear red, white, or tan
Third Degree Burns
- extends through the epidermis and dermis and into the subcutaneous layer
- may not be painful initially because of the destruction of nerve endings
- may appear white or black and leathery
- often requires skin grafts
What is the most common form of cancer?
Skin Cancer
How many types of skin cancer are there?
Three
Basal Cell Carcinoma
- Most Common Type
- Seldom metastasizes so its the least dangerous
- Arises from cells of the stratum basale, typically on the nose or face
-Lesion first appears as a small shiny bump, then it develops a central depression and a beaded pearly edge - Risk factors include UV light exposure, having light colored skin, advanced age, and a suppressed immune system
Squamous Cell Carcinoma
- Arises in the epidermis and is slow growing
- Often occurs on scalp, forehead, backs of hands, tops of ears
- Has raised red scaly appearance
- Some forms may metastasize
- Risk factors include UV light exposure, having light colored skin, advanced age, and suppressed immune system
Malignant Melanoma
- Most deadly of all skin cancers
- Develops from melanocytes, sometimes from those in a preexisting mole
- Metastasizes quickly, often fatal when not treated early
- Risk is greatest in individuals who had severe sunburns as children
