Chapter 6
Integument
Outline:
Anatomy-skin has two principal parts. 1. epidermis 2. dermis-below it is hypodermis
Physiology-functions- 1. regulation of temp 2. protection 3. sensation 4. excretion 5.
immunity 6. blood reservoir 7. vitamin D synthesis.
Epidermis
 composed of stratified squamous epithelium
 four types of cells-Keratinocytes-waterproof, Melanocytes-melanin pigment,
Langerhans immune cells, Merkel cells-nerve endings for touch
 five layers- Stratum basale or S. germinatum, Stratum spinosum, Stratum
granulosum, Stratum lucidum, Stratum corneum see pages 146-148 Martini.
 Skin cancer-see page 151 of Martini. Detection-A-asymmetry B-border, C-color,
D-diameter. Three types a) basal cell carcinoma, b) squamous cell carcinomas, c)
malignant melanoma-cancerous melanocytes grow rapidly and metastasize.
Dermis-thick in palms and soles, two regions-i) papillary region-areolar connective tissue
ii) reticular-dense irregular connective tissue
Hypodermis-present deep to the dermis known as superficial fascia or subcutaneous
layer. It has pressure sensitive nerve endings called Pacinian corpuscles
Skin color-melanin-dark pigment, carotene-yellow orange pigment, and hemoglobinblood color
Albinism-inability to produce melanin results albinism
Vitiligo-partial or complete loss of melanocytes
Epidermal ridges-dermal papillae forms epidermal ridges
Epidermal derivatives
Hair
primary function- protection. Anatomy----consists of shaft- on the skin surface, rootbelow skin surface
inner medulla -both shaft and root has inner medulla having two or three rows of
poyhedral cells having pigment granules and air sacs
-cuticle of the hair-outermost layer consists of single layer of scale like cells
root of the hair- follicle surrounds root having internal and external root sheaths
bulb-base of each follicle having indentation called papilla-containing areolar
connective tissue
sebaceous(oil)glands and arrector pilli muscles-associated with hairs
http://www.webmd.com/skin-problems-and-treatments/hair-loss/science-hair
Glands
three types-i) sebaceous-secretes sebum-a mixture of fat, cholesterol, proteins and
inorganic salts, ii) sudoriferous-eccrine-throughout the skin, apocrine-on axilla, pubic and
areolae of the breast, iii) ceruminous-produce waxy secretion called cerumen, iv)
mammory glands
Nails
Hard keratinized cells, has nail body and nail root. L
Wound healing:
Epidermal and deep wound healing-inflammatory phase, migratory phase, proliferative
phate and maturation phase
Thermoregulation: homeostasis
Burns-three degrees.
Aging-thinning of skin, wrinkling, reduced melanocyte activity.
development
http://www.articleinput.com/e/a/title/The-seven-basic-functions-of-human-skin/