The Integumentary System A_M1

skin is a covering for the deeper tissues; helps regulated body temperature through perspiration

skin

made up of two basic layers: epidermis and dermis

the outermost layer is made up of epithelial cells with no blood vessels (avascular)

the true skin and is the lower layer where connective tissue and blood vessels are found

has four cell types and five layers

keratinocytes, merkel cells, melanocytes, and langerhas cells

produce keratin

touch receptors

produce the protein melanin for protecting against ultraviolet rays

macrophages (protective defense cells) that protect the skin against microorganisms

stratum germinativum, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum

the deepest layer of the epidermis

8-10 cell layers thick

where the keratinization process of changing the soft cytoplasm of the cells into a harder substance occurs

found only on the hands and soles of the feet

the surface layer of the epidermis which has dead cells rich in keratin

the thicker, inner layer of the skin

ridges in the top layer of the dermis next to the epidermis which help with gripping and are used for identification (fingerprints)

the superficial fascia located below the dermis

include the hair, nails, sudoriferous (sweat) glands, sebaceous (oil) glands, and their ducts

distributed over most of the body; the length, thickness, type, and color vary; the root is emdedded in the skin

hard structures on the dorsal surface of the distal phalanges (toes and fingers)

99% water with only small amounts of salt and organic materials (waste products); provide minimal excretion for the body

similar to sweat glands

produce a thick, oily substance, sebum, to lubricate the skin