Integumentary System Flashcards
Epidermis is composed of 4 different cell types, what are they?
Keratinocytes, melanocytes, merkel cells, langerhans
What are the layers of the keratinocytes?
stratum basale/germinativum: mitosis (melanocytes)
stratum spinosum
stratum granulosum
stratum lucidum
stratum corneum: dead cells
Melanocytes:
what are these?
-function
-what causes an increase in its production?
What: pigment producing cells (melanin)
- ability to synthesize melanin depends on the ability of the melanocytes to produce the enzymes tyrosinase.
- everyone has the same amount of melanocytes but efficiency of production is different.
Function: protect from UV rays
Exposure to UV rays increases production of melanin
Merkel Cells:
-function
Langerhans Cells:
-function
function: mechanoreceptors found in the dermis
langerhan function:
-immunological cells responsible for recognizing foreign Ags. They bind to their surface, process it, and send it to the LN.
What makes up the dermis?
What makes up the subcutaneous tissue
Mostly composed of collagen
immune cells
nerves
blood vessels
SubQ tissue:
- fat and CT
- eccrine glands and deep hair follicles extend into this layer
What are the two types of sweat glands? Describe:
- where found on body
- function
- open up onto skin or hair follicle?
- what is their secretion?
Eccrine & Apocrine
Eccrine:
- located over entire body surface
- function is to transport sweat to body sufrace to regulate body temperature.
- open up to skin surface.
- secrete sweat.
Apocrine:
- located in the axilla, genitals, areola, anus, areas where there is hair
- not sure of function.
- open up onto hair follicle
- secrete more of an oily substance, sterile and odorless until mixed with bacteria
Describe pathophysiology of apocrine gland.
Apocrine gland; starts off relatively small but its granules gradually increase with an oily substance. Upper portion of gland breaks down (oil and cell) this is secreted into the gland. Cell loses a portion of itself as it excretes its substance.
Sebacous gland:
- secretes what?
- location
- secreted onto skin surface of hair follicle?
- function
secretes sebum; lipids, cholesterol, & other substances.
located over the entire skin surface except for the palms, soles, and sides of feet.
secretes onto hair follicle
function: lubricate hair and skin
The entire hair structure consists of?
hair follicle and hair shaft
sebaceous gland
arrrector pili
sometimes an apocrine gland
What determines hair color?
what is the medical term for cuticle?
which structure of the nail is responsible for growth of the nail?
melanocytes determine hair color
cuticle = eponychium
nail matrix is responsible for growth of the nail
Make sure to evaluate what 3 things with all rashes?
What is the difference between primary and secondary lesions
Appearance, distribution, symmetry
Primary lesions arise from previously normal skin, secondary lesion are created be another process such as scratching or infection of a lesion that was their previously.
Primary lesions, which ones are flat, raised, and raised with something in them?
Flat: macule, patch
Raised: papule, plaque, nodule, tumor, wheal
Raised with something inside: vesicle, bulla, pustule.
What are the secondary lesions?
Scales, crust, erosions, ulcer, fissures, atrophy, scar.
Define each of the following:
- excoriation
- comedones
- Milia
- cyst
- abscess
- burrow
Excoriation: localized damage to the skin d/t scratching and consists of linear or pinpoint erosions or crusts.
Comedones: plug of sebacous and keritinized material lodged in opening of hair follicle. Black head is open and white head is closed.
Milia: small superficial keratin cyst with no visible opening. seen in kids who sweat.
Cyst: cavity lined with epithelium containing fluid or keratin.
Abscess: infected lesion surrounded by a membrane and filled with exudate
Burrow: narrow, elevated tortuous channel produced by a parasite.
Define each of the following:
- lichenification
- umbilicated
- telangiectasia
- petechia
- ecchymosis
- keratin horn
lechenification: thickening of the epidermis with increased skin markings d/t persistant scratching
Umbilicated: contains rounded depression in the center.
telangiectasia: dilated superficial blood vessels
petechia: circumscribed deposit of blood less than 0.5cm
ecchymosis: circumscribed deposit of blood greater than 0.5cm (bruise)
Keratin horn: accumulation of abnormal keratin which is usually rough on palpation and difficult to remove.
