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The Integumentary System

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The Integumentary System CHAPTER 5: THE INTEGUMENTARY SYSTEM Copyright © 2010 Pearson Education, Inc. OVERALL SKIN STRUCTURE 3 LAYERS Copyright © 2010 Pearson Education, Inc. Figure 5.1 Skin structure. Hair shaft Dermal papillae Epidermis Subpapillary vascular plexus Papillary layer Pore Appendages of skin Dermis Reticular • Eccrine sweat layer gland • Arrector pili muscle Hypodermis • Sebaceous (oil) gland (superficial fascia) • Hair follicle Nervous structures • Hair root • Sensory nerve fiber Cutaneous vascular • Pacinian corpuscle plexus • Hair follicle receptor Adipose tissue (root hair plexus) Copyright © 2010 Pearson Education, Inc. EPIDERMIS 4 (or 5) LAYERS Copyright © 2010 Pearson Education, Inc. Figure 5.2 The main structural features of the skin epidermis. Keratinocytes Stratum corneum Stratum granulosum Epidermal Stratum spinosum dendritic cell Tactile (Merkel) Stratum basale Dermis cell Sensory nerve ending (a) Dermis Desmosomes Melanocyte (b) Melanin granule Copyright © 2010 Pearson Education, Inc. DERMIS 2 LAYERS Copyright © 2010 Pearson Education, Inc. Figure 5.3 The two regions of the dermis. Dermis (b) Papillary layer of dermis, SEM (22,700x) (a) Light micrograph of thick skin identifying the extent of the dermis, (50x) (c) Reticular layer of dermis, SEM (38,500x) Copyright © 2010 Pearson Education, Inc. Figure 5.3a The two regions of the dermis. Dermis (a) Light micrograph of thick skin identifying the extent of the dermis, (50x) Copyright © 2010 Pearson Education, Inc. Q1: The type of gland which secretes its products onto a surface is an _______ gland. 1) Endocrine 2) Exocrine 3) Merocrine 4) Holocrine Copyright © 2010 Pearson Education, Inc. Q2: The embryonic tissue which gives rise to muscle and most connective tissue is… 1) Ectoderm 2) Endoderm 3) Mesoderm Copyright © 2010 Pearson Education, Inc. Q3: A melanocyte would be found in the _____ of the epidermis. 1) Stratum basale 2) Stratum spinosum 3) Stratum granulosum 4) Stratum lucidum 5) Stratum corneum 6) Reticular layer 7) Papillary layer Copyright © 2010 Pearson Education, Inc. Q4: The main cell type in the epidermis is the... 1) Melanocyte 2) Langerhans Cell 3) Merkel Cell 4) Dendritic Cell 5) Keratinocyte Copyright © 2010 Pearson Education, Inc. Q5: The bulk of the dermis is the ______ layer. 1) Epidermal 2) Hypodermal 3) Reticular 4) Papillary Copyright © 2010 Pearson Education, Inc. SKIN COLOR 3 PIGMENTS Copyright © 2010 Pearson Education, Inc. SKIN APPENDAGES Copyright © 2010 Pearson Education, Inc. CUTANEOUS GLANDS Copyright © 2010 Pearson Education, Inc. Figure 5.5 Cutaneous glands. Sweat pore Sebaceous gland Dermal Eccrine connective gland tissue Sebaceous gland duct Hair in hair follicle Duct Dermal connective tissue Secretory cells (a) Photomicrograph of a (b) Photomicrograph of sectioned sebaceous a sectioned eccrine gland (220x) gland (220x) Copyright © 2010 Pearson Education, Inc. A sweat gland in your axilla (armpit) is which type of gland? 1) Sebaceous 2) Apocrine 3) Eccrine Copyright © 2010 Pearson Education, Inc. HAIR FOLLICLES Copyright © 2010 Pearson Education, Inc. Figure 5.6a Structure of a hair and hair follicle. Follicle wall • Connective tissue root sheath • Glassy membrane • External epithelial root sheath • Internal epithelial root sheath Hair shaft Hair • Cuticle • Cortex • Medulla Arrector pili (a) Diagram of a cross section of Sebaceous a hair within its follicle gland Hair root Hair bulb Copyright © 2010 Pearson Education, Inc. Figure 5.6b Structure of a hair and hair follicle. Follicle wall • Connective tissue root sheath • Glassy membrane • External epithelial root sheath • Internal epithelial root sheath Hair • Cuticle • Cortex Hair shaft • Medulla Arrector (b) Photomicrograph of a cross pili section of a hair and hair Sebaceous follicle (250x) gland Hair root Hair bulb Copyright © 2010 Pearson Education, Inc. Figure 5.6c Structure of a hair and hair follicle. Hair shaft Arrector pili Sebaceous gland Hair root Follicle wall Hair bulb • Connective tissue root sheath • Glassy membrane • External epithelial root sheath • Internal epithelial root sheath Hair root • Cuticle • Cortex • Medulla Hair matrix Hair papilla Melanocyte Subcutaneous adipose tissue (c) Diagram of a longitudinal view of the expanded hair bulb of the follicle, which encloses the matrix Copyright © 2010 Pearson Education, Inc. Figure 5.6d Structure of a hair and hair follicle. Follicle wall • Connective tissue root sheath Hair shaft • Glassy membrane • External epithelial root sheath • Internal epithelial root sheath Arrector Hair root pili • Cuticle Sebaceous • Cortex gland • Medulla Hair root Hair matrix Hair bulb Hair papilla Subcutaneous adipose tissue (d) Photomicrograph of longitudinal view of the hair bulb in the follicle (160x) Copyright © 2010 Pearson Education, Inc. Which layer of a hair follicle wall is thickest? 1) Connective tissue root sheath 2) External epithelial root sheath 3) Internal epithelial root sheath Copyright © 2010 Pearson Education, Inc. NAILS Copyright © 2010 Pearson Education, Inc. Figure 5.7 Structure of a nail. Lateral Lunule nail fold (a) Free edge Body Eponychium of nail of nail (cuticle) Proximal nail fold Nail bed Root of nail Nail matrix (b) Hyponychium Phalanx (bone of fingertip) Copyright © 2010 Pearson Education, Inc. What is the scientific name for the cuticle? 1) Eponychium 2) Hyponychium 3) Lunule 4) Nail matrix Copyright © 2010 Pearson Education, Inc. FUNCTIONS Copyright © 2010 Pearson Education, Inc. DISEASES (“HOMEOSTATIC IMBALANCES”) Copyright © 2010 Pearson Education, Inc. SKIN CANCER Copyright © 2010 Pearson Education, Inc. Figure 5.8 Photographs of skin cancers. Copyright © 2010 Pearson Education, Inc. True or false: all skin cancers start out looking like moles. 1) True 2) False Copyright © 2010 Pearson Education, Inc. SKIN BURNS Copyright © 2010 Pearson Education, Inc. Figure 5.10 Partial thickness and full thickness burns. 1st degree 3rd burn degree burn 2nd degree burn (a) Skin bearing partial (b) Skin bearing full thickness burn (1st and thickness burn 2nd degree burns) (3rd degree burn) Copyright © 2010 Pearson Education, Inc. Figure 5.9 Estimating the extent and severity of burns using the rule of nines. Totals 4 1 /2 % Anterior and posterior head and neck, 9% Anterior and posterior upper limbs, 18% Anterior Anterior and posterior 4 1 /2 % trunk, 4 1 /2 % 18% trunk, 36% 9% 9% (Perineum, 1%) Anterior and posterior lower limbs, 36% 100% Copyright © 2010 Pearson Education, Inc. A patient playing with a lighter and a can of hairspray experienced second- and third- degree burns covering his entire left arm. What percent of the body was burned? 1) 4.5 % 2) 9% 3) 18% 4) 8% Copyright © 2010 Pearson Education, Inc. .
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