Integumentary System PDF

Skin and Body Membranes Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Skin and Body Membranes Function of body membranes Line or cover body surfaces Protect body surfaces Lubricate body surfaces Senses the outside...

Skin and Body Membranes Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Skin and Body Membranes Function of body membranes Line or cover body surfaces Protect body surfaces Lubricate body surfaces Senses the outside world Langerhan cells Meissner corpuscles Pacinian corpuscle Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.1  Thermoregulation Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.1  Vitamin D Synthesis The epidermal layer of human skin synthesizes vitamin D when exposed to UV radiation Vitamin D is essential for normal absorption of calcium and phosphorous, which are required for healthy bones. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.1  Classification of Body Membranes Epithelial membranes Cutaneous membrane Mucous membrane Serous membrane Connective tissue membranes Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.2  Cutaneous Membrane Cutaneous membrane = skin A dry membrane Outermost protective boundary Superficial epidermis Keratinized stratified squamous epithelium (keratin-waterproofing protein found in hair & skin) Underlying dermis Mostly dense connective tissue Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.3  Mucous Membranes Surface epithelium Type depends on site Underlying loose connective tissue (lamina propria) Lines all body cavities that open to the exterior body surface Often adapted for absorption or secretion Figure 4.1b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.4  Serous Membranes Surface simple squamous epithelium Underlying areolar connective tissue Lines open body cavities that are closed to the exterior of the body Serous layers separated by serous fluid Figure 4.1c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.5  Serous Membranes Specific serous membranes Peritoneum Pleura Pericardium Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.6  Connective Tissue Membrane Synovial membrane Connective tissue only Lines fibrous capsules surrounding joints Figure 4.2 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.7 Checkpoint! How do the body locations of serous and mucous membranes differ? Where would you find a synovial membrane? Doctor who specializes in conditions involving the skin? Essential for normal absorption of calcium and phosphorous, which are required for healthy bones.  Skin Structure Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.10a  Layer of Epidermis Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Dermis Papillary layer Projections called dermal papillae Pain receptors Capillary loops Reticular layer Blood vessels Glands Nerve receptors Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.13a  Hypodermis its a layer directly below the dermis serves to connect the skin to the underlying fascia of the bones and muscles. Well-vascularized, loose, areolar Hypodermis connective tissue and adipose tissue,. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Normal Skin Color Determinants Melanin Yellow, brown or black pigments Carotene Orange-yellow pigment from some vegetables Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.14  Hemoglobin Red coloring from blood cells in dermis capillaries Oxygen content determines red coloring  Figure 4.4 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.13b  Redness or erythema Pallor, or blanching Jaundice Cyanosis Bruises or black- and –blue marks Checkpoint What cell type is most abundant in the epidermis? Which layer of the epidermis produces new epidermal cells? Excess shedding of scales from the superficial layer of the skin of the scalp causes dandruff, what is the name of the skin layer What pigments determine skin color? Appendages of the Skin Cutaneous glands All exocrine glands Sebaceous glands Sweat glands  Sebaceous glands Produce oil: Lubricant for skin; Kills bacteria Ducts that empty into hair follicles Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.15  Sweat glands Widely distributed Two types Eccrine Apocrine Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.16  Sweat glands Apocrine Found in densely hairy areas Controlled by Nervous and Hormone Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.16  Sweat and Its Function Mostly water Some metabolic waste (urea, uric acid) Fatty acids and proteins (apocrine only) dissipate excess heat Excretes waste products Acidic nature inhibits bacteria growth Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.17  Hair Produced by hair bulb hard keratinized epithelial cells Melanocytes can provide pigment for color Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.18  Hair Anatomy Central medulla Cortex surrounds medulla Cuticle on outside of cortex Most heavily keratinized Figure 4.7b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.19  Associated Hair Structures Hair follicle Dermal and epidermal sheath surround hair root Arrector pili Smooth muscle Sebaceous gland Sweat gland Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.20  Appendages of Skin Nails Scale-like modifications of epidermis Heavily keratinized Lack of pigment makes them colorless Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.21  Nail Structures Free edge Body Root of nail Heavily keratinized Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 4.22 Checkpoint! The epidermis is a layer of ________ tissue The dermis is is a layer of _________ tissue The skin is thickest on the ______ of the hands and the ____ of the feet As cells move up from the basement membrane, they eventually _____ Checkpoint! The protein material of hair and nails is ____ Cells lose their nuclei and become compact and brittle in the __________ Cells of the epidermis that are capable of dividing are found in the ________ An absence of melanin produces a condition called ______ Checkpoint! A bluish tinge to the skin is called ________ Goose bumps are caused by the ________ muscle The eponychium is the _______ Skin Homeostatic Imbalances Infections Athletes foot - caused by fungal infection  Boils and carbuncles - caused by bacterial infection Cold sores - caused by virus  Contact dermatitis –itching, redness, and swelling of the kin, progressing to blistering Impetigo- pink, water-filled, raised lesions that develop a yellow crust and eventually rupture Psoriasis- a chronic condition characterized by over production of skin cells that result in reddened epidermal lesions covered with dry, silvery scales that itch, burn, crack and sometimes bleed.  Burn is tissue damage and cell death caused by intense heat, electricity, UV radiation (sunburn), or certain chemicals First- degree burn Second degree burn – epidermis and the upper region of the dermis Third- degree burns – entire thickness of theskin Skin cancer Basal cell carcinoma – least malignant and most common Cells of the stratum basale, altered that they cannot form keratin The cancer lesions occur most often on sun- exposed areas of the face and appear as shiny, dome-shaped nodules that later develop a central ulcer with a “pearly” beaded edge  Squamous cell carcinoma – arises from the cells of the stratum spinosum The lesions appear scaly, reddened papule that gradually forms a shallow ulcer with a firm, raised border Appears most often on the scalp, ears, dorsum of the hands, and lower lip It grows rapidly and metastasizes to adjacent lymph nodes  Malignant melanoma – cancer of the melanocytes Can begin wherever there is pigment It arises from accumulated DNA damage in skin cell and usually appears as a spreading brown to black patch Metastasizes rapidly to surrounding lymph and blood vessels Checkpoint! The type 1 herpes simplex virus causes? The nail is modification of ________ Sweat odor is caused by _________