18 terms

Integumentary System chapter 5

Integumentary system composition
skin, glands, hair, nails
Skin layers
epidermis (outer), dermis (inner)
stratfied squamous epithelium; bottom layer is the stratum basale - closest to the blood supply, actively mitotic, contains melanocytes; outer layer is the stratum corneum - continually sloughed off, replaced by cells from deeper layers
aka Stratum Corium; composed of connective tissue with blood vessels, nerves, and accessory structures
subcutaneous tissue; anchors the skin to the underlying muscles; connective tissue with an abundance of adipose (cushion, insulation, energy)
Skin color
dependant on the amount of melanin produced by the melanocytes in the stratum basale; carotene - provides yellow pigment; blood - capillaries give a pink color
divided into visible shaft and the root which is embedded in the skin and surrounded by the follicle
Arrector pili muscle
make the hair "stand on end"
kerantinized stratum coreum; derived from the stratum basale in the nail bed
Sebaceous glands
oil glands; associated with hair follicles; secrete sebum; help keep the hair and skin soft and pliable and help prevent water loss
Sudoriferous glands
sweat glands
Merocrine sweat glands
most numerous type - open to the surface of the skin through sweat pores and secrete perspiration in response to nerve stimulation and/or heat
Apocrine sweat glands
larger than merocrine glands; limited to axillae and external genitalia where they open to hair follicles; become active at puberty and are stimulated in response to painm emotional stress, and sexual arousal
Ceruminous glands
modified sweat glands; found only in external auditory canal; secrete cerumen (ear wax)
Skin protects
against water loss; invading organisms; ultraviolent light; other injuries
Skin senses
via receptors to detect information about the invironment; also serves as a means of communication between individuals
Skin regulates
body temperture via 1 constriction/dilation of blood vessels that affect the amount of heat that escapes from skin 2 sweat glands that are stimulated in response to heat and are inactive in cold temperatures 3 adipose in subcutaneous tissue helps to insulate the body
Skin produces
vitamin D - precursors for vitamin D are found in the skin and when the skin is exposed to ultraviolet light these precursors are converted into active vitamin