section 5.4-5.6 Flashcards
what is a polymer made of the amino acid tyrosine?
melanin
what causes the pinkish hue of fair skin and lives in red blood cells in dermal capillaries?
hemoglobin
what yellowish-orange pigment can be converted into vitamin a for vision and epidermal health?
carotene
where could you find carotene in the body?
stratum coreum and the subcutaneous layer
what are hair, hair follicles, nails, sweat glands, and sebaceous glands classified as?
skin appendages
what can be indicated by a blueness of skin?
respiratory or cardiovascular problems
what can be indicated by pallor or blanching?
emotional stress or anemia
what can be indicated by redness of skin?
blushing, fever, inflammation, allergy
what can be indicated by yellowness of skin?
jaundice
what can red/purple/green/yellow marks on the skin indicate?
bruises
what can a brown/black “necklace” or bruises indicate?
insulin resistance or elevated blood glucose
what are flexible strands produced by hair follicles?
hair
what is composed of dead, keratinized cells and is made of hard keratin?
hair
what kind of keratin dominates hairs and nails, is tougher, and is more durable?
hard keratin
what are the chief regions of hair?
root and shaft
what hair region is embedded in skin?
root
what hair region projects over the surface?
shaft
what are the 3 concentric layers of the hair?
medulla, cortex, cuticle
what is the central core of the hair that contains large cells and air spaces and is absent from fine hair?
medulla
what’s the bulky layer surrounding the medulla that consists of several layers of flattened cells?
cortex
what layer of hair is the outermost layer and has cells that overlap like shingles on a roof?
cuticle
what fold down from the epidermal surface into the dermis?
hair follicles
what is derived from the epidermis and has 2 components: the external and internal root sheath?
epithelial root sheath
what do the deep ends of follicles expand to become?
hair bulb
what is a knot of sensory receptors that wraps around each hair bulb?
hair follicle receptor
what forms the external layer of the follicle wall?
peripheral connective tissue sheath
what is a junction of the fibrous sheath and the epithelial root sheath?
glassy membrane
what is the basement membrane of follicle epithelium?
glassy membrane
what is composed of the dividing cells of the hair follicle and lies adjacent to hair papilla?
hair matrix
what are hair matrix cells replenished by?
stem cells
what are bundles of smooth muscle cells that cause goosebumps?
arrector pilli
what disease occurs when too many follicles enter the resting phase at the same time?
Tellogen effuvium
what disease is genetically determined and changes the response of hair follicles to androgens
make pattern baldness
what forms a protective covering on the dorsal surface of toes on fingers?
nails
what is the bed of epidermal cells that the nail rests on called?
nail bed
what is the outward concavity of the mail that may signal iron deficiency?
koilonychia
what is the proximal nail fold projecting onto the nail body?
cuticle
what is the thickened region beneath the free edge at which dirt and degree accumulate?
hyponychium
