BIO 210 ch. 5 Integumentary System
Cuticle
Stratum corneum from the nail fold that extends onto the nail body
Lanugo
Delicate, unpigmented hair that develops and covers the fetus by the fifth or sixth month
Cyanosis
A bluish skin color caused by a decrease in blood oxygen content
Corn
A cone-shaped structure that forms over bony prominences
Third-degree Burn
A full-thickness burn in which the epidermis and dermis are completely destroyed and deeper tissue may be involved
Dermis
A layer of connective tissue beneath the epidermis
Papillary Layer
A layer of the dermis that is areolar connective tissue with thin fibers that are somewhat loosely arranged.
Matrix
A mass of epithelial cells inside the hair bulb which produces the hair
ABCDE Rule
A method of detecting melanoma: Asymmetry (one side of the lesion doesn't match the other side) Border irregularity (edges are ragged, notched, or blurred) Color (pigmentation not uniform) Diameter (greater than 6m) Evolving (lesion changes over time)
First-degree Burn
A partial-thickness burn involving only the epidermis
Second-degree Burn
A partial-thickness burn that damages the epidermis and dermis
Albinism
A recessive genetic trait that causes a deficiency or an absence of melanin
Cuticle
A single layer of cells, with hard keratin, that forms the hair surface
Psoriasis
A skin condition characterized by increased cell division in the stratum corneum that sloughs to produce large, silvery scales
Lunula
A small part of the nail matrix that can be seen through the nail body as a whitish, crescent-shaped area at the base of the nail
Actinic Keratosis
A small, scaly, crusty bump that arises on the surface of the skin which, if untreated, progresses to squamous cell carcinoma 2%-5% of the time
Callus
A thickened area of the skin that occurs when the number of layers of the stratum corneum greatly increases due to friction or pressure
Nail
A thin plate, consisting of layers of dead stratum corneum cells with hard keratin, located on the distal ends of the digits of humans and other primates
Stratum Lucidum
A thin, clear zone above the stratum granulosum, consisting of several layers of dead cells with indistinct boundaries
Moderate Burn
A third-degree burn of 2%-10% of the BSA or second-degree burn of 15%-25% of the BSA.
Minor Burn
A third-degree burn of less than 2% or a second-degree burn of less than 15% of the BSA
Major Burn
A third-degree burn over 10% or more of the BSA A second-degree burn over 25% or more of the BSA A second- or third-degree burn of the hands, feet, face, genitals, or anal region
Hair Follicle
A tubelike invagination of the epidermis into the dermis from which the hair develops
Carotene
A yellow pigment found in plants, such as carrots and corn. Humans ingest it and use it as a source of Vitamin A.
Jaundice
A yellowish skin color that can occur when the liver is damaged by a disease such as viral hepatitis
Acne
An inflammation of the hair follicles and sebaceous glands
Intramuscular Injection
An injection into a muscle deep to the subcutaneous tissue, accomplished by inserting a needle at a 90-degree angle to the skin
Intradermal Injection
An injection into the dermis, such as for the tuberculin skin test
Subcutaneous Injection
An injection into the fatty tissue of the subcutaneous tissue, such as for an insulin injection
Sebum
An oily, white, lipid-rich substance produced by sebaceous glands. It lubricates the hair and the surface of the skin, which prevents drying and protects against some bacteria.
Langerhans Cells
Cells that are part of the immune system
Keratinocytes
Cells that produce keratin, which makes them hard. They are responsible for the ability of the epidermis to resist abrasion and reduce water loss
Dermis
Connective tissue with fibroblasts, a few adipose cells, and macrophages
Cornified Cells
Dead cells with a hard protein envelope filled with the protein keratin
Moles
Elevations of the skin that are variable in size and are often pigmented and hairy. They are aggregations ("nests") of melanocytes in the epidermis or dermis.
Nail Bed
Epithelial tissue under the nail
Accessory Skin Structures
Hair, smooth muscles called the arrestor pili, glands, and nails
Erythma
Increased redness of the skin resulting from increased blood flow through the skin
Burn
Injury to tissue caused by heat, cold, friction, chemicals, electricity or radiation
Melanocytes
Irregularly-shaped cells with many long processes that extend between the keratinocytes of the stratum basale and the stratum spinosum. These cells contribute to skin color.
Striae (stretch marks)
Lines of scar tissue that may develop if dermis ruptures when skin is overstretched, leaving lines that are visible through the epidermis
Lamellar Bodies
Lipid-filled, membrane-bound organelles found in the stratum spinosum
Terminal Hairs
Long, coarse, pigmented hairs that replace the lanugo of the scalp, eyelids, and eyebrows near the time of birth
Mammary Glands
Modified apocrine sweat glands located in the breasts
Ceruminous Glands
Modified eccrine sweat glands that produce cerumen (earwax)
Epithelial Root Sheath
Part of the hair follicle with an external and internal part. At the opening of the follicle, it has all the strata found in thin skin, but deeper in the follicle, the number of cells decrease until at the hair bulb only the stratum basale is present
Hair Papilla
Projection of the dermis into the hair bulb which contains blood vessels that provide nourishment to the cells of the matrix
Dermal Papillae
Projections underlying thick skin in parallel, curving ridges that shape the overlying epidermis into ridges
Vellus Hairs
Short, fine, usually unpigmented hairs that replace the lanugo everywhere except the scalp, eyelids, and eyebrows near the time of birth
Sebaceous Glands
Simple or compound alveolar glands located in the dermis, usually connected by a duct to the superficial part of the hair follicle
Eccrine Sweat Glands
Simple, coiled tubular glands located in almost every part of the skin, most numerous in the palms and the soles.
Apocrine Sweat Glands
Simple, coiled tubular glands that produce a thick secretion rich in organic substances. They open into hair follicles, but only in the axillae and genitalia.
Thick Skin
Skin found in areas subject to friction. It has all five epithelial strata, and the stratum corneum has many layers of cells.
Thin Skin
Skin that is more flexible than thick skin. Each stratum contains fewer layers of cells than are found in thick skin; the stratum granulosum frequently consists of only one or two layers of cells, and the stratum lucid generally is absent.
Desquamate
Slough off, as older cells which are pushed to the surface by the formation of new cells
Freckles
Small, discrete areas of the epidermis with a uniform brown color. They are the result of an increased amount of melanin in the stratum basale keratinocytes.
Arrector Pili
Smooth muscle cells associated with each hair follicle
Merkel Cells
Specialized epidermal cells associated with the nerve endings responsible for detecting light touch and superficial pressure
Hair Bulb
The base of the root of the hair
Cortex
The bulk of the hair--consists of cells containing hard keratin
Medulla
The central axis of the hair, consisting of two or three layers of cells containing soft keratin
Stratum Basale
The deepest layer of the epidermis, consisting of a single layer of cuboidal or columnar cells
Melanin
The group of pigments responsible for skin, hair and eye color
Stratum Spinosum
The layer superficial to the stratum basal, consisting of 8-10 layers of many-sided cells
Melanoma
The least common, but most deadly, type of skin cancer, which arises from melanocytes
Reticular Layer
The main layer of the dermis. It is composed of dense irregular connective tissue.
Basal Cell Carcinoma
The most common type of skin cancer which arises from cells in the stratum basale
Stratum Corneum
The most superficial layer of the epidermis, consisting of 25 or more layers of dead squamous cells joined by desmosomes
Epidermis
The most superficial layer of the skin--it consists of epithelial tissue
Root of the hair
The part of the hair below the surface of the skin
Shaft of the hair
The part of the hair that protrudes above the surface of the skin
Nail Root
The part of the nail covered by skin and extending distally from the nail matrix
Dermal Root Sheath
The portion of the dermis that surrounds the epithelial root sheath
Keratinization
The process of cells moving from the deeper epidermal layers to the surface, changing shape and chemical composition--they become filled with keratin
Excretion
The removal of waste products from the body
Age spots
The result of an increase in the number of melanocytes
Cleavage (or tension) Lines
The result of elastic and collagen fibers being oriented more in some directions than in others
Squamous Cell Carcinoma
The second-most common type of skin cancer that arises from cells in the stratum spinosum and can s\appear as a wartlike growth; a persistent, scaly, red patch; an open sore; or an elevated growth with a central depression
Growth Stage
The stage of hair production when stem cells in the matrix cells give rise to transit amplifying cells that differentiate, become keratinized and die
Resting Stage
The stage of hair production when there is no hair growth and the hair is held in the hair follicle
Strata
The stages of keratinization (plural of stratum)
Stratum Granulosum
The stratum that consists of two to five layers of diamond-shaped cells. Its name comes from the nonmembrane-bound protein granules of keratohyalin, which accumulate in the cytoplasm of the cell.
Integumentary System
The system that consists of the skin and accessory structures, such as hair, glands, and nails
Nail Body
The visible part of the nail
Subcutaneous Tissue (Hypodermis)
Tissue that attaches the skin to underlying bone and muscle and supplies it with blood vessels and nerves.
Warts
Uncontrolled growths of the epidermis caused by the human Papillomavirus
Melanosomes
Vesicles produced by the Golgi apparatus of the melanocyte