what is this?
what is this?
what is this?
what is a vesicle?
what is a papule?
body's largest organ?
skin has two layers
All people have same number of melanocytes. T/F
From the basal layer new cells migrate up and flatten into the outer?
Skin color is derived from three sources?
mainly from the brown pigment melanin. 2) Also from the yellow orange tones of the pigment carotene. 3) the red purple tones in the underlying vascular bed. All people have skin of varying shades of brown, yellow, and red; the relative proportion of these shades affect the prevailing color. Skin color is further modified by the thickness of skin and by the presence of edema.
inner supportive layer consisting mostly of connective tissue or collagen. Tough fibrous protein that enables skin to resist tearing. The nerves sensory receptors blood vessels and lymphatics lie in the dermis. Appendages from the epidermis such as hair follicles sebaceous glands and sweat glands are embedded in the dermis.
is adipose tissue which is made up of lobules of fat cells. The subcutaneous tissue stores fat for energy, provides insulation for temperature control, and aids in protection by its soft cushioning effect. Also the loose subcutaneous layer gives skin its increased mobility over structures underneath.
Around the hair follicle is the?
two types of hair- vellus hair?
glands produce a protective lipid substance sebum is secreted through the hair follicles. Sebum oils lubricate skin and hair and forms an emulsion with water that retards water loss from skin. sebacious glands are everywhere except on palms and soles. They are most abundant in scalp, forehead, face, and chin.
There are two types of sweat glands
eccrine glands- coiled tubules that open directly onto the skin surface and produce a dilute saline solution called sweat. The evaporation of sweat reduces body temp. They are mature in 2 month old infant.
approcrine gland- thick milky secretion in hair follicle. location- mainly axillae, anogenital area, nipples, and navel, and are vestigial in humans. Become active in puberty, secretion occurs with emotional and sexual stimulation.
Functions of skin
1) protection- injury, thermal, chemical, light wave sources.
2) prevent penetration- invasions of microorganisms, & prevent loss of water and electrolytes in body.
3) perception- skin sensory surface touch, pain, temp, and pressure
4) temp regulation- allow heat to dissipate through sweat glands and heat storage through subcutaneous insulation
5) identification- facial structures, hair color, finger prints
6) wound repair- skin allows cell repairment
7) absorption and secretion
8) production of vit D
several skin conditions among blacks:
aging in skin-
subjective data for skin, hair, nails
tiny punctate hemorrhage 1 to 3 mm round and discrete, dark red purple, or brown in color. Cause by bleeding from superficial capillaries; will not blanch. May indicate abnormal clotting factors. In dark skinned people petechiae are best visualized in areas of lighter melanization. When the skin is black or very dark brown, petechiae cannot be seen in the skin. thrombocytopenia, subacute bacterial endocarditis, and other septicemias, are characterized by petechiae in mucous membranes as well as on the skin.
tinea pedis ringworm of foot
inner edge of nail elevates; nail bed greater than 180 degreees. Distal phalanx looks rounder and wider. association with physiology of platelet production. Lung inflam, bronchial tumor, heart defects with R to L shunt, fragmented platelets become trapped in the fingertip vasculature, releasing platelet derived growth factor and promoting frowth of vessels which shows as clubbing. It develops SLOWLY over years. If the primary disease is treated clubbing can reverse.
basal cell carcinoma
usually starts as skin colored papule ( may be deeply pigmented with a pearly translucent top) and overlying telangiectasia (broken blood vessel) Then develops round pearly border with central red ulcer, or looks like a large open pore with central yellowing. MOST COMMON FORM OF SKIN CANCER, slow but inexorable growth. Basal cell cancers occur on sunexposed areas of face, ears, scalp, and shoulders.
squamous cell carcinoma
serious arthritis cardiac or neuro sequalia. Caused by spirochete bacterium carried by black or dark brown deer tick. 1st stage has distinctive bull eye, red macular or papular rash, in 50% of cases. The rash radiates from site with some central clearing and is usually located in axillae, middriff, inguina, or behind knees, with regional lymphadenopathy. Rash fades in 4 weeks. untreated individuals may have disseminated disease with fatigue, anorexia, fever, chills, joint or muscle aches. Antibiotics are tx.
herpes simplex virus
Aids related Kaposi Sarcoma