BIO100 Chptr 6 Flashcards
alb-
alb-, white: albinism—lack of pigment in skin, hair, and eyes.
cut-
cut-, skin: subcutaneous—beneath the skin.
derm-
derm-, skin: dermis—inner layer of the skin.
epi-
epi-, upon, after, in addition: epidermis—outer layer of the skin.
follic-
follic-, small bag: hair follicle—tubelike depression in which a hair develops.follic-
hol-
hol-, entire, whole: holocrine gland—gland that discharges the entire cell containing the secretion.
kerat-
kerat-, horn: keratin—protein produced as epidermal cells die and harden.
melan-
melan-, black: melanin—dark pigment produced by certain cells.
por-
por-, passage, channel: pore—opening by which a sweat gland communicates to the skin’s surface.
seb-
seb-, grease: sebaceous gland—gland that secretes an oily substance.
sudor-
sudor-, sweat: sudoriferous glands—exocrine glands that secrete sweat.
skin-cutaneous membrane
The skin is composed of several types of tissues. Also known as the cutaneous membrane
epidermis
the skin includes two distinct layers: epithelial tissue overlying connective tissue. The outer layer, called the epidermis (ep″i-der′mis), is composed of stratified squamous epithelium. The inner layer, or dermis
dermis
the skin includes two distinct layers: The inner layer, or dermis (der′mis), is thicker than the epidermis and is made up of connective tissue containing collagen and elastic fibers, smooth muscle tissue, nervous tissue, and blood.
basement membrane
A basement membrane anchored to the dermis by short fibrils separates the two skin layers.
subcutaneous (sub″ku-ta′ne-us) layer, or hypodermis
Beneath the dermis, masses of areolar and adipose tissues bind the skin to underlying organs. These tissues are not part of the skin.
Intradermal injections
are administered into the skin.
Subcutaneous injections and intramuscular injections, administered into muscles, are also called hypodermic injections.
Subcutaneous injections
are administered through a hollow needle into the subcutaneous layer beneath the skin
Subcutaneous injections and intramuscular injections, administered into muscles, are also called hypodermic injections.
keratinization (ker″ah-tin″i-za′shun).
The cell membranes of older skin cells thicken and develop many desmosomes that fasten them to each other . At the same time, these older cells begin to harden, in a process called keratinization (ker″ah-tin″i-za′shun). Strands of tough, fibrous, waterproof keratin proteins are synthesized and stored in the cell.
stratum corneum
the horny outer layer of the skin. (Dead skin cells that flake off when ya rub with a towel)
melanocytes - melanin
melanocytes produce the pigment melanin (mel′ah-nin) from the amino acid tyrosine in organelles called melanosomes. Melanin provides skin color. Melanin also absorbs ultraviolet radiation in sunlight, which would otherwise cause mutations in the DNA of skin cells and other damaging effects.
stratum corneum
Stratum corneum-
Outermost layer - layer 1
Many layers of keratinized, dead epithelial cells that are flattened and non-nucleated
Stratum lucidum
Stratum lucidum (only present in thick skin)
layer - 2
Between stratum corneum and stratum granulosum on soles and palms
Cells appear clear; nuclei, organelles, and cell membranes are no longer visible
Stratum granulosum
Stratum granulosum
Beneath the stratum corneum - layer 3
Three to five layers of flattened granular cells that contain shrunken fibers of keratin and shriveled nuclei
Stratum spinosum
Stratum spinosum
Beneath the stratum granulosum - layer 4
Many layers of cells with centrally located, large, oval nuclei and developing fibers of keratin; cells becoming flattened
Stratum basale
Stratum basale (basal cell layer)
Deepest layer - layer 5
A single row of cuboidal or columnar cells that divide and grow; this layer also includes melanocytes
eumelanin (u-mel′ah-nin)
Skin color is due largely to melanin, primarily the brownish-black eumelanin (u-mel′ah-nin) in the epidermis.
Differences in skin color result from differences in the amount of melanin produced by the melanocytes, which is controlled by several genes.
pheomelanin
The reddish-yellow pheomelanin (fe″o-mel′ah-nin) is found in certain locations, such as the lips.
Differences in skin color result from differences in the amount of melanin produced by the melanocytes, which is controlled by several genes.
cutaneous carcinomas
(basal cell carcinoma or squamous cell carcinoma)
The two most common kinds of skin cancer -
which are sometimes called nonmelanoma skin cancer. These cancers are carcinomas that begin in the cells that cover or line an organ.
Nails
are protective coverings on the ends of the fingers and toes. Each nail consists of a nail plate that overlies a surface of skin called the nail bed.
dermal papillae
are small, nipple-like extensions (or interdigitations) of the dermis into the epidermis. At the surface of the skin in hands and feet, they appear as epidermal or papillary ridges (colloquially known as fingerprints).
hair follicle
Each hair develops from a group of epidermal stem cells at the base of a tubelike depression called a hair follicle (hār fol′ĭ-kl). These stem cells originate from a region near the bottom of the hair follicle, known as the hair bulge, and migrate downward. The follicle also contains the hair root, which can extend from the surface into the dermis and sometimes into the subcutaneous layer.
arrector pili muscle
A bundle of smooth muscle cells, forming the arrector pili muscle, attaches to each hair follicle. When the muscle contracts, a short hair in the follicle stands on end.
Sebaceous glands
contain groups of specialized epithelial cells and are usually associated with hair follicles. They are holocrine glands, and their cells produce globules of a fatty material that accumulate, swelling and bursting the cells. The resulting mixture of fatty material and cellular debris is called sebum.
sebum
an oily secretion of the sebaceous glands.
androgenic alopecia
Pattern baldness - it is associated with testosterone, an androgenic (male) hormone
Sweat (swet) glands
- also called sudoriferous glands
Sweat glands are a type of exocrine gland, which are glands that produce and secrete substances onto an epithelial surface by way of a duct.
merocrine sweat glands
are coiled tubular glands that discharge their secretions directly onto the surface of the skin. The clear secretion produced by merocrine glands is termed sweat or sensible perspiration.
apocrine (ap′o-krin) sweat glands
Apocrine glands open into the hair follicle, leading to the surface of the skin. Apocrine glands develop in areas abundant in hair follicles, such as on your scalp, armpits and groin.
Eccrine glands
occur over most of your body and open directly onto the surface of your skin.
acne vulgaris
is the formation of comedones, papules, pustules, nodules, and/or cysts as a result of obstruction and inflammation of pilosebaceous units (hair follicles and their accompanying sebaceous gland). Acne develops on the face and upper trunk. It most often affects adolescents.
The primary means of body heat loss is
body heat protection and loss
radiation - by which infrared heat rays escape from warmer surfaces to cooler surroundings.
conduction (body heat protection and loss)
In conduction, heat moves from the body directly into the molecules of cooler objects in contact with its surface.
convection (body heat protection and loss)
As air becomes heated, it moves away from the body, carrying heat with it, and is replaced by cooler air moving toward the body. This type of continuous circulation of air over a warm surface is convection
evaporation (body heat protection and loss)
When the body temperature rises above normal, the nervous system stimulates merocrine sweat glands to release sweat onto the surface of the skin. As this fluid evaporates (changes from a liquid to a gas), it carries heat away from the surface, cooling the skin.
hyperthermia
the condition of having a body temperature greatly above normal.
Hypothermia
is a medical emergency that occurs when your body loses heat faster than it can produce heat, causing a dangerously low body temperature. Normal body temperature is around 98.6 F (37 C)
Inflammation
is a normal response to injury or stress.
first-degree burn -First (superficial)
red and dry, but without blisters (such as mild sunburn) top layer of skin (epidermis) temporary skin color changes
second-degree burn
red, swollen, and blistered skin top and middle layers of skin (dermis) may cause an increase in skin thickness
third-degree burn
white and charred-looking epidermis, dermis, and subcutaneous (fat) tissues extensive skin damage, including thicker skin and scars as it heals
fourth-degree burn
charred skin with possible exposed bone skin, tendons, nerves, and possibly muscles may cause permanent damage to affected area, requiring amputations
fith-degree burn
charred, white skin and exposed bone skin, tendons, muscles, and bones permanent body damage, amputation, and organ damage possible
sixth-degree burn
loss of skin with exposed bone extends to the bones same as fifth-degree burns, but with possible fatalities
allograft
a tissue graft from a donor of the same species as the recipient but not genetically identical.
