Due in Lab 1. Skeletal System 33-34 2. Skeletal System 26 3. PreLab 6 Due next week in lab - Scientific America Article Select one article to read and complete article summary Cell Defenses and the Sunshine Vitamin (Summary in Case Study 19-20) Skin Deep (Summary in Case Study 21-22) Sex and the Secret Nerve (Instructor website) The Naked Truth (Instructor website)
The Integumentary System
Epidermis Dermis Hair shaft Papillary layer Reticular layer Hypodermis (superficial fascia) Nervous structures Sensory nerve fiber Pacinian corpuscle Hair follicle receptor (root hair plexus) Dermal papillae Subpapillary vascular plexus Pore Appendages of skin Eccrine sweat gland Arrector pili muscle Sebaceous (oil) gland Hair follicle Hair root Cutaneous vascular plexus Adipose tissue Copyright 2010 Pearson Education, Inc. Figure 5.1
Structure of the Skin One of the body s largest organs 2 main layers Epidermis Dermis Derivatives Hair Nails Glands Sebaceous Sudoriferous Ceruminous
Structure of the Skin Epidermis 4-5 main layers Stratum corneum Surface layer, dead cells Stratum germinativum Dividing cells Melanin
Epidermis Dermis Hair shaft Papillary layer Reticular layer Hypodermis (superficial fascia) Nervous structures Sensory nerve fiber Pacinian corpuscle Hair follicle receptor (root hair plexus) Dermal papillae Subpapillary vascular plexus Pore Appendages of skin Eccrine sweat gland Arrector pili muscle Sebaceous (oil) gland Hair follicle Hair root Cutaneous vascular plexus Adipose tissue Copyright 2010 Pearson Education, Inc. Figure 5.1
Structure of the Skin Dermis Deep to epidermis Contains Connective tissue Nerve endings Blood vessels Hair follicles Skin glands Hypodermis
Epidermis Dermis Hair shaft Papillary layer Reticular layer Hypodermis (superficial fascia) Nervous structures Sensory nerve fiber Pacinian corpuscle Hair follicle receptor (root hair plexus) Dermal papillae Subpapillary vascular plexus Pore Appendages of skin Eccrine sweat gland Arrector pili muscle Sebaceous (oil) gland Hair follicle Hair root Cutaneous vascular plexus Adipose tissue Copyright 2010 Pearson Education, Inc. Figure 5.1
Structure of the Skin Epidermal derivatives Hair Structure Root Shaft Follicle Pigments Melanin, brown, yellow Gray?
Epidermis Dermis Hair shaft Papillary layer Reticular layer Hypodermis (superficial fascia) Nervous structures Sensory nerve fiber Pacinian corpuscle Hair follicle receptor (root hair plexus) Dermal papillae Subpapillary vascular plexus Pore Appendages of skin Eccrine sweat gland Arrector pili muscle Sebaceous (oil) gland Hair follicle Hair root Cutaneous vascular plexus Adipose tissue Copyright 2010 Pearson Education, Inc. Figure 5.1
Structure of the Skin Epidermal derivatives Hair cont. Functions Insulation Protection Sensation Psychosocial Nails
Structure of the Skin Epidermal derivatives Glands Sebaceous Associated with hair follicles Secrete oil Fats, cholesterol, proteins, salts Functions
Structure of the Skin Epidermal derivatives Glands Sudoriferous Tubular glands, numerous on palms and soles Secrete sweat Water, salts, urea, uric acid, amino acids, lactic acid, ascorbic acid Functions
Structure of the Skin Epidermal derivatives Glands Ceruminous Secrete ear wax Functions
Functions of the Skin Sensation Protection Chemical, physical/mechanical, biological Excretion Vitamin D production Temperature regulation
Stimulus Body temperature rises Information sent along the afferent pathway to control center Receptors Temperature-sensitive cells in skin and brain Control Center (thermoregulatory center in brain) Afferent pathway BALANCE Efferent pathway Information sent along the efferent pathway to effectors Effectors Sweat glands Sweat glands activated Response Evaporation of sweat Body temperature falls; stimulus ends Response Body temperature rises; stimulus ends Stimulus Body temperature falls Effectors Skeletal muscles Receptors Temperature-sensitive cells in skin and brain Shivering begins Information sent along the efferent pathway to effectors Efferent pathway Control Center (thermoregulatory center in brain) Afferent pathway Information sent along the afferent pathway to control center Copyright 2010 Pearson Education, Inc. Figure 1.5
Skin Disorders Color can be an important indicator of health Pigmentation Paleness/redness Cyanosis Jaundice
Addison s disease
Jaundice
Cyanosis
Skin Diseases Acne Impetigo Psoriasis Decubitus ulcers Sunburn Skin cancer Basal cell carcinoma Squamous cell carcinoma Melanoma Systemic lupus erythematosis Warts
Acne
Impetigo
Psoriasis
Decubitus ulcers
Sunburn
Cancer Basal cell carcinoma Malignant melanoma
Burns Causes Heat Chemicals Electricity Radiation Dangers Fluid and plasma protein loss shock Infection Circulation Kidney damage Scarring
Burns Classification Rule of nines Treatment
Burns First degree Epidermal damage only Localized redness and pain Second degree Epidermal and upper dermal damage Blistering, edema and pain
1st degree burn 2nd degree burn (a) Skin bearing partial thickness burn (1st and 2nd degree burns) Copyright 2010 Pearson Education, Inc. Figure 5.10a
Burns Third degree Entire thickness of skin damaged Gray-white, cherry red, or black No initial edema or pain (nerve endings destroyed) Skin grafting usually necessary
3rd degree burn (b) Skin bearing full thickness burn (3rd degree burn) Copyright 2010 Pearson Education, Inc. Figure 5.10b
Burns Critical if: >25% of the body has second-degree burns or worse >10% of the body has third-degree burns Face, hands, or feet have third-degree burns
4 1 / 2 % 4 1 / 2 % Anterior trunk, 18% 4 1 / 2 % Totals Anterior and posterior head and neck, 9% Anterior and posterior upper limbs, 18% Anterior and posterior trunk, 36% 9% 9% (Perineum, 1%) Anterior and posterior lower limbs, 36% 100% Copyright 2010 Pearson Education, Inc. Figure 5.9
Burns Treatment Cleaning and debridement Fluid therapy Protection Grafting Prevention of infection May require very high calorie and high protein diet
Burns Treatment
Skin: Developmental Aspects Advanced age Decreased blood flow to skin Thinning of epidermis Loss of subcutaneous fat Less collagen and elastin Fewer melanocytes Gray hair Reduced glandular activity