WEEK 5 Integumentary system.pdf

WEEK 4: The Integumentary System KATELYN ANNE L. SOLERO, RMT INSTRUCTOR Objectives This presentation aims to discuss the following: 1. Membranes 2. Layers and Functions of the Skin 3. Skin pigments 4. Accessory structures: Skin glands, hair and nails 5. Homeostatic Imbalan...

WEEK 4: The Integumentary System KATELYN ANNE L. SOLERO, RMT INSTRUCTOR Objectives This presentation aims to discuss the following: 1. Membranes 2. Layers and Functions of the Skin 3. Skin pigments 4. Accessory structures: Skin glands, hair and nails 5. Homeostatic Imbalances of the Skin K.SOLERO 2024 – HAPP111 - PRELIMS Classification of Body Membranes Epithelial Membrane - Cutaneous Membrane - Mucous Membrane - Serous Membrane Connective Tissue Membrane - Synovial Membrane K.SOLERO 2024 – HAPP111 - PRELIMS Cutaneous Membranes Cutaneous membrane = skin Outermost protective boundary Epidermis = Superficial layer - Keratinized stratified squamous epithelium keratin-waterproofing protein found in hair & skin Dermis - Mostly dense connective tissue K.SOLERO 2024 – HAPP111 - PRELIMS 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 K.SOLERO 2024 – HAPP111 - PRELIMS 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 Parietal layer – outer layer Visceral layer – inner layer Serous fluid - secreted by mesothelium Pleura – Lungs Pericardium - Heart Peritoneum - Abdomen K.SOLERO 2024 – HAPP111 - PRELIMS Synovial Membranes Connective tissue only Lines fibrous capsules surrounding joints Synoviocytes – secretes fluid Synovial fluid - lubricates and nourishes the cartilage K.SOLERO 2024 – HAPP111 - PRELIMS Integumentary System composed of the skin, hair, oil and sweat glands, nails, and sensory receptors. Dermatology – study of the skin SKIN - largest organ (16% of body weight) - K.SOLERO 2024 – HAPP111 - PRELIMS Integumentary System Functions of the Integumentary System: 1. Regulates body temperature. 2. Stores blood. 3. Protects body from external environment. 4. Detects cutaneous sensations. 5. Excretes and absorbs substances. 6. Synthesizes vitamin D. K.SOLERO 2024 – HAPP111 - PRELIMS Layers of the Skin 1. Epidermis 2. Dermis 3. Hypodermis Hypodermis K.SOLERO 2024 – HAPP111 - PRELIMS Epidermis EPIDERMIS consists of keratinized stratified squamous epithelium, which protects underlying tissues. SUPERFICIAL LAYER of the skin. Composed of 5 layers From superficial to deep 1. Stratum Corneum 2. Stratum Lucidum 3. Stratum Granulosum 4. Stratum Spinosum 5. Stratum Basale K.SOLERO 2024 – HAPP111 - PRELIMS Epidermis ✓Stratum Corneum 25 to 30 rows of dead, fat keratinocytes that contain mostly keratin. ✓Stratum Lucidum Present only in skin of Lips, fingertips, palms, and soles; consists of 3 to 5 rows of clear, fat, dead keratinocytes with large amounts of keratin. ✓Stratum Granulosum 3 to 5 rows of flattened keratinocytes, in which organelles are beginning to degenerate; cells contain the protein keratohyalin, which converts tonofilaments into keratin, and lamellar granules, which release a lipid- rich, water-repellent secretion. K.SOLERO 2024 – HAPP111 - PRELIMS Epidermis ✓Stratum Spinosum 8 to 10 rows of many-sided keratinocytes with bundles of tonofilaments; includes armlike processes of melanocytes and Langerhans cells. ✓ Stratum Basale Deepest layer, composed of a single row of cuboidal or columnar keratinocytes. 4 types of cells can be found within the Stratum Basale: 1. Keratinocytes 2. Melanocytes 3. Merkel Cells 4. Langerhans Cells K.SOLERO 2024 – HAPP111 - PRELIMS Epidermis Keratinocytes Main cells of epidermis and are considered the building blocks of the protein keratin Melanocytes Produce pigment melanin to protect against UV radiation and gives skin its color Merkel Cells Also known as nerve cells for touch reception Langerhans Cells Known as non-pigmented granular dendrocytes for macrophagic cells that ingest bacteria and other foreign debris. K.SOLERO 2024 – HAPP111 - PRELIMS Skin pigments Melanin - Yellow to brown to black pigment by melanocyte. Carotene - Yellow-orange pigment from Vitamin A. Hemoglobin - Red coloring - oxygen-carrying pigment in red blood cells. K.SOLERO 2024 – HAPP111 - PRELIMS Conditions associated with skin pigments Albinism - inability of an individual to produce melanin. Melanin is missing from their hair, eyes, and skin. Vitiligo - the partial or complete loss of melanocytes from patches of skin produces irregular white spots. K.SOLERO 2024 – HAPP111 - PRELIMS Dermis DERMIS consists of connective tissue (areolar connective tissue and dense irregular connective tissue) SECOND DEEPER LAYER of the skin is composed of a strong connective tissue containing collagen and elastic fibers. K.SOLERO 2024 – HAPP111 - PRELIMS Dermis Papillary Region The superficial portion of the dermis 1/5. consists of areolar connective tissue with thin collagen and fine elastic fibers contains dermal ridges that house capillaries, Meissner corpuscles, and free nerve endings. Reticular Region The deeper portion of the dermis 4/5. consists of dense irregular connective tissue with bundles of thick collagen and some coarse elastic fibers. Spaces between fibers contain some adipose cells, hair follicles, nerves, sebaceous glands, and sudoriferous glands. K.SOLERO 2024 – HAPP111 - PRELIMS Cutaneous Glands of Dermis Exocrine glands in the integumentary system 1. Sebaceous Glands 2. Sweat Glands 3. Ceruminous Glands 4. Mammary Glands K.SOLERO 2024 – HAPP111 - PRELIMS Cutaneous Glands of Dermis Sebaceous Glands (oil glands) Found all over the skin except on palms and soles secrete an oily substance called sebum a mixture of triglycerides, cholesterol, proteins, and inorganic salts. Sebum coats the surface of hairs and helps keep them from drying and becoming brittle. K.SOLERO 2024 – HAPP111 - PRELIMS Cutaneous Glands of Dermis Sudoriferous glands (sweat glands) Secretion evaporates and cools the body Numerous in palms, sole, armpits, pubic regions. Mammary glands Found within the breast which are specialized sweat glands that secrete milk (2) Types 1. Merocrine sweat gland 2. Apocrine sweat gland K.SOLERO 2024 – HAPP111 - PRELIMS Cutaneous Glands of Dermis K.SOLERO 2024 – HAPP111 - PRELIMS Cutaneous Glands of Dermis Ceruminous gland produce a waxy lubricating secretion. The secretory portions of ceruminous glands lie in the subcutaneous layer, deep to sebaceous glands. The combined secretion of the ceruminous and sebaceous glands is a yellowish material called cerumen, or earwax. Cerumen, together with hairs in the external auditory canal, provides a sticky barrier that impedes the entrance of foreign bodies and insects. K.SOLERO 2024 – HAPP111 - PRELIMS  Hypodermis SUBCUTANEOUS OR HYPODERMIS is the deepest layer of the skin composed of fatty tissues. Thermal Insulation, energy storage and shock absorption This layer consists of areolar and adipose tissues. Fibers that extend and attaches to underlying fascia, the connective tissue around muscles and bones. serves as a storage depot for fat and contains large blood vessels that supply the skin. Also contains nerve endings that are sensitive to pressure K.SOLERO 2024 – HAPP111 - PRELIMS Hair are present on most skin surfaces EXCEPT the palms, palmar surfaces of the fingers, the soles, and plantar surfaces of the feet. Each hair is composed of columns of dead, keratinized epidermal cells bonded together by extracellular proteins. K.SOLERO 2024 – HAPP111 - PRELIMS  Parts of the Hair Hair Shaft - the superficial portion of the hair, projects above the surface of the skin. Hair Root - penetrates into the dermis, and sometimes into the subcutaneous layer. Hair Follicle - Surrounding the root of the hair. Hair Bulb - The base of each hair follicle Accessory structure: Arrector pili muscle – “goose bumps” or “gooseflesh” because the skin around the shaft forms slight elevations Sebaceous gland Sweat gland K.SOLERO 2024 – HAPP111 - PRELIMS  Hair Medulla - center Cortex – surrounds medulla Cuticle - outermost layer, most heavily keratinized Hair cycle 1. Rest 2. Growth 3. Rest 4. Shedding K.SOLERO 2024 – HAPP111 - PRELIMS  Nails are plates of tightly packed, hard, dead, keratinized epidermal cells that form a clear, solid covering over the dorsal surfaces of the distal portions of the digits. K.SOLERO 2024 – HAPP111 - PRELIMS Parts of the Nails Nail body (plate) - visible portion of the nail. Free edge – white ends Nail root – buried in a fold of skin Lunula – whitish, crescent-shaped area Hyponychium / Nail bed – secures the nail to the fingertip Eponychium / Cuticle – margin (lateral border) of the nail wall. Nail matrix – mitosis for growth K.SOLERO 2024 – HAPP111 - PRELIMS Homeostatic Imbalances of the Skin Fungal Infections of the Skin Tinea pedis – Athlete’s foot Tinea corporis – Ringworm on the body Tinea cruris – jock’s itch Tinea capitis – Ringworm on the scalp Tinea pedis Tinea corporis Tinea cruris Tinea capitis K.SOLERO 2024 – HAPP111 - PRELIMS Homeostatic Imbalances of the Skin Caused by bacterial infections: Boils and Carbuncles Impetigo K.SOLERO 2024 – HAPP111 - PRELIMS Homeostatic Imbalances of the Skin Caused by viral infections: Cold sores K.SOLERO 2024 – HAPP111 - PRELIMS Homeostatic Imbalances of the Skin Allergies Psoriasis K.SOLERO 2024 – HAPP111 - PRELIMS Homeostatic Imbalances of the Skin Burns - Tissue damage & cell death - Caused by heat, electricity, UV radiation, or chemicals Associated dangers Dehydration Electrolyte imbalance Circulatory shock Burns are considered critical if: >25% of body has 2nd degree burns >10% of the body has 3rd degree burns 3rd degree burns of the face, hands, or feet K.SOLERO 2024 – HAPP111 - PRELIMS Burns Body is divided into 11 areas for quick estimation of extent of burns. Rule of 9’s ADULT CHILD Head – 9% Head – 18% Arms – 9% each Arms – 9% each Legs – 18% each Legs – 13.5% each Chest – 18% Chest – 18% Back – 18% Back – 18% Groin – 1% Groin – 1% K.SOLERO 2024 – HAPP111 - PRELIMS Burn First Degree of Burn Second Degree of Burn Third Degree of Burn Only epidermis is damaged Epidermis and upper dermis are Destroys entire skin layer Skin is red and swollen damaged Burn is gray-white or black Skin is red with blisters K.SOLERO 2024 – HAPP111 - PRELIMS Homeostatic Imbalances of the Skin Skin Cancer - most common type of cancer Cancer - abnormal cell mass Benign - Does not spread Malignant - Metastasized (moves) to other parts of the body K.SOLERO 2024 – HAPP111 - PRELIMS Homeostatic Imbalances of the Skin Basal Cell Carcinoma Squamous Cell Carcinoma Malignant Melanoma Least malignant Metastasizes to lymph nodes Most deadly of skin cancers Most common Early removal allows a good Cancer of melanocytes chance of cure Metastasizes rapidly to lymph and blood vessels Detection uses ABCD rule K.SOLERO 2024 – HAPP111 - PRELIMS ABCD Rule A = Asymmetry Two sides of pigmented mole do not match B = Border irregularity Borders of mole are not smooth C = Color Different colors in pigmented area D = Diameter Spot is larger then 6 mm in diameter K.SOLERO 2024 – HAPP111 - PRELIMS ABCD Rule A = Asymmetry Two sides of pigmented mole do not match B = Border irregularity Borders of mole are not smooth C = Color Different colors in pigmented area D = Diameter Spot is larger then 6 mm in diameter K.SOLERO 2024 – HAPP111 - PRELIMS