NR 283 Exam Review 2
Skin – chapter 8
Layers of skin:
*varies in layer of thickness
• Epidermis
a. Avascular/no nerves
b. Consists of 5
... [Show More] layers
c. Hair follicles
d. glands
• Dermis
a. Elastic fibers
b. Collagen fibers
c. Flexibility & strength of the skin
d. Contains nerves & blood vessels
• Subcutaneous tissue (hypodermis)
a. Connective tissue
b. Fat cells
c. Blood vessels
d. Nerves
e. Macrophages
f. fibroblasts
Keratin: waterproofing of the skin
Melanin: skin pigment- determines color of skin
Albinisim: lack melatonin production
• lacks pigmentation in iris
• White hair
• White skin – susceptible to skin cancer
• Autosomal rec
Vitiligo: small areas of hypopigmentation
Melasma: overproduction of melanin
• Patches of darker skin
Dermis…
Sensory receptors:
• Pressure
• Touch
• Pain
• Heat
• Cold
Appendages of the skin:
• Hair follicles
• Sebaccous glands
• Sweat glands
Functions of skin:
• First line of defense
• Prevents excessive fluid loss
• Controls body temp
• Active in sensory perception
• Synthesizes vitamin D
Skin lesions:
Causes:
• Systemic disorders- liver disease
• Systemic infection- chicken pox
• Allergies to ingest foods/drugs
• Localized factors- exposure to toxins
Types:
• Location
• Length of time lesion has been present
• Changes to occurring over time
• Physical appearance- color, elevation, texture, type of exudate
• Presence of pain or pruritus (itching)
Macules- freckles, sun spots; small, flat lesions
Papule- firm, elevated warts
Nodule- fatty tumor, benign
Pustule- elevated lesion filled w/ pus (pimple)
Vesicle- raised blister, filled w/serous fluid
Plaque- buildup of dead skin tissue, psoriasis (silvery color)
Crust- opened, dried vesicle, empitygo
Lichenification- leather-like appearance
Keloid- too much collagen
Fissures- cracks in a line, athlete’s foot
Ulcer- lack of blood supply (longer healing period), open sore
Erosion- has a glistening appearance, a cut
Pemphigus- watery blisters; mouth/genitals
Comedone- bacteria under skin, blackhead/whitehead
a. Contact dermatitis- systemic; poison ivy, allergic to gold, nickel, etc
b. Irritant contact dermatitis; bleach (immersing hand in it for a long period of time)
c. Uticaria; hives [Show Less]