Chapter 5 Integumentary System Latest Update 100% Pass

Chapter 5 Integumentary System Latest Update 100% Pass The integumentary system consists of... skin, hair, glands, and nails Functions of the integumentary system include: protection, sensation, temperature regulation, vitamin D production, and excretion epidermis stratified squamous epithelium divided into five strata five strata of epidermis include: stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum stratum basale Bottom layer of the epidermis. cuboidal shaped cells. cells undergoing mitosis in this layer stratum spinosum layer above the stratum basale - some cells still dividing stratum granulosum consists of cells filled with granules of keratin stratum lucidum consists of a layer of dead, transparent -thick skin only stratum corneum consists of many layers of dead squamous cells - top layer of epidermis thick skin has all five epithelial strata; found in palms of hands and soles of feet (no hair) stratum lucidum is found in this skin thin skin contains fewer cell layers per stratum, and the stratum lucidum is usually absent; hair is found here melanin Produced by melanocytes inside melanosomes and then transfer the melanin to keratinocytes. The size and distribution of melanosomes determine skin color. Melanin production is determined genetically but can be influenced by ultraviolet light (tanning) and hormones. carotene an ingested plant pigment, can cause the skin to appear yellowish increased blood flow produces a ________ skin color red decreased blood flow causes _______ skin pale cyanosis decreased oxygen content in the blood resulting in a bluish color of the skin dermis connective tissue divided into two layers (papillary layer & reticular layer) papillary layer of dermis has projections called dermal papillae and is composed of loose connective tissue that is well supplied with capillaries. Responsible for finger prints. areolar connective tissue reticular layer of dermis the main layer, being much thicker. It's dense irregular connective tissue consisting mostly of collagen. skin is overstretched, striae (stretch marks) occur. Dense irregular connective tissue subcutaneous tissue (hypodermis) located beneath the dermis, it's loose connective tissue that contains collagen and elastic fibers, NOT A PART OF SKIN! this tissue attaches the skin to underlying structures and is a sit of fat storage arrector pilli muscle smooth muscles that when contracted cause hair to "stand on end" and produce "gooseflesh" or "goosebumps" sebaceous glands produce sebum, which oils the hair and the surface of the skin eccrine or merocrine sweat glands produce sweat, which cools the body. Secretions are primarily water. apocrine sweat glands produce an organic secretion that can be broken down by bacteria to cause body oder. Found in genital and axillary regions. the skin protects against... abrasion and UV lights, prevents the entry of microorganisms, helps regulate body temperature, and prevents water loss (keratin). sensation of skin the skin contains sensory receptors for pain, temperature, hot, cold, and pressure that allow proper response to the environment temperature regulation of integumentary system through dilation and constriction of blood vessels, the skin controls heat loss from the body sweat glands, produce sweat, which evaporates and lowers body temperature what does vitamin D do? increases blood calcium levels by promoting calcium uptake from the small intestine, calcium release from bone, and the reduction of calcium loss from the kidneys smooth muscles that produce "goose bumps" when they contract and are attached to hair follicles are called arrector pili layer of dermis responsible for fingerprints and footprints papillary layer layer of dermis responsible for most of the structural strength of the skin reticular layer coiled, tubular glands that secrete a hyposmotic fluid that cools the body; most numerous in the palms of the hands and soles of the feet eccrine sweat gland the skin helps maintain optimum calcium and phosphate levels in the body by participating in the production of vitamin D secretions from these coiled, tubular glands are broken down by bacteria to produce body odor; found in the axillae; in the genitalia, and around the anus apocrine sweat glands