MC 1 Integumentary

University:
College
Course:
Medical Laboratory Science
Academic year:

2025
Views:

96

Pages:

4
Author:

JP Cua

MC 1 ANATOMY AND PHYSIOLOGY 1 OBJECT INTEGUMENTARY SYSTEM ● HEAVIEST & LARGEST ORGAN OF INTEGUMENTARY SYSTEM 16% OF THE BODY ● INTEGUMENTARY SYSTEM COMPOSED OF SKIN, HAIR, NAILS AND GLANDS (APPENDAGES OF THE SKIN) THE SKIN DIVIDED 3 LAYERS 1. EPIDERMIS 2. DERMIS 3. HYPODERMIS FUNCTIONS OF THE SKIN 1. RESISTANCE & PROTECTION AGAINST TRAUMA AND INFECTION 2. BARRIER AGAINST ULTRAVIOLET LIGHT 3. VITAMIN D SYNTHESIS 4. SENSORY RECEPTOR 5. THERMORECEPTOR THROUGH SWEATING EPIDERMIS / ECTODERM 1. IT IS THIN VASCULAR SUPERFICIAL LAYER OF THE SKIN 2. COMPOSED OF KERATINIZED STRATIFIED SQUAMOUS EPITHELIUM CONSISTING OF FOUR DISTINCT CELL TYPE AND FIVE LAYERS 3. OUTER PORTION OF THE SKIN IS EXPOSED TO THE EXTERNAL ENVIRONMENT AND FUNCTIONS IN PROTECTION EPIDERMIS LAYERS CELL OF THE EPIDERMIS 1. KERATINOCYTES - MOST OF THE SKIN, PRODUCE OF THE FIBUROUS PROTEIN KERATIN (VITAL TO SKINS PROTECTIVE BARRIER FUNCTION) 2. MELANOCYTES - PRODUCE THE BROWN PIGMENT MELANIN (GIVE COLOR TO HAIR AND SKIN) 3. LANGERHAN'S CELL (DENDRITIC) EPIDERMAL MACROPHAGES THAT HELP ACTIVE THE IMMUNE SYSTEM 4. MERKELL CELLS (TACTILE) FUNCTION AS TOUCH RECEPTOR IN ASSOCIATION WITH ACCESSORY MC 1 ANATOMY AND PHYSIOLOGY NERVE ENDINGS LAYERS OF EPIDERMIS. STRATUM BASALE (BASAL LAYER) ● DEEPEST EPIDERMAL LAYER FIRMLY ATTACHED TO THE DERMIS ● CONSISTS OF A SINGLE ROW OF THE YOUNGEST KERATINOCYTES ● CELL UNDERGO RAPID DIVISION, HENGE ITS ALTERNATE NAME, STRATUM GERMINATIVUM STRATUM SPINOSUM (PICKY LAYER) ● CELLS CONTAINS A WEBLIKE SYSTEM OF INTERMEDIATE FILAMENTS ATTACHED TO DESMOSOMES ● MELANIN GRANULES AND LANGERHAN'S CELL ARE ABUNDANT IN THE LAVER STRATUM GRANULOSUM (GRANULAR LAYER) ● THIN; THERE TO FIVE CELL LAYERS IN WHICH DRASTIC CHANGES IN KERATINOCUTE APPEARANCE OCCURS ● KERATOHYALINE AND LAMELLATED GRANULES ACCUMULATE IN THE CELL OF THIS LAYER. STRATUM LUCIDUM (CLEAR LAYER) ● THIN, TRANSPARENT BAND SUPERFICIAL TO THE STRANTOM GRANULOSUM ● CONSISTS OF A FEW ROWS OF FLAT, DEAD KERATINOCYTES PRESENT ONLY IN THICK SKIN STRACTUM CORNEUM (HORNEY LAYER) ● OUTERMOST LAVER OR KERATINIZED CELLS ● ACCOUNTS FOR THREE QUARTERS OF THE EPIDERMAL THICKNESS ● FUNCTIONS: WATER PROOFING ● PROTECTION FROM ABRASION AND PENETRATION ● RENDERS THE BODY RELATIVELY INSENSITIVE TO BIOLOGICAL CHEMICALS AND PHYSICAL ASSAULTS DERMIS / MESODERM 1. SECOND MAJOR SKIN REGION CONTAINING STRONG, FLEXIBLE CONNECTIVE TISSUES 2. CELL TYPES INCLUDE FIBOROBLASTS, MACROPHAGES, AND 2 OCCASIONALLY MAST CELLS AND WHITE BLOOD CELL 3. PROVIDES BLOOD SUPPLY FOR EPIDERMIS, CONTAINS SENSORY RECEPTORS. ANCHORS EPIDERMIS IN PLACE 4. COMPARED OF TWO LAYER PAPILLARY & RETICULAR LAYERS OF EPIDERMIS PAPILLARY LAYER / DERMIS 1. AROLAL CONNECTIVE TISSUE WITH COLLAGEN AND ELASTIC FIBERS 2. ITS SUPERIOR SURFACE CONTAINS PEGLIKE PROJECTIONS CALLED DERMAL PAPILLAE 3. DERMAL PAPILLAE CONTAIN CAPILLARY LOBPS, MEISSNER'S CORPUSCLES, AND FREE NERVE ENDINGS 1. DERMAL PAPILLAE: TINY, FINGER-LIKE PROJECTIONS POUND AT SURFACE PAPILLARY LAYER CONTAIN TWO IMPORTANT STRUCTURE A. CAPILLARIES: TINY BLOOD VESSELS PROVIDE OXYGEN AND NUTRIENTS TO DERMIS AND EPIDERMIS. B. TACTILE (MEISSNER) CORNUCLES: RESPOND TO LIGHT TOUCH STIMULI - NUMEROUS IN AREAS WHERE SENSATION IS PRIMARY FUNCTION SUCH AS FINGERTIPS, LIPS, AND PACE LAYERS OF THE DERMIS 2. RETICULAR LAYER / DERMIS: THICKER AND DEEP TO PAPILLARY LAYER. SEPARATES DERMIS FROM HYPODERMIS MAINLY IRREGULARLY ARRANGED COLLAGEN BUNDLE (STRENGTH). ELASTIC FIBER ALLOW DERMIS TO RETURN TO ORIGINAL SHAPE AND SIZE AFTER STRETCHING. PROTEOGLYCANS DRAW WATER INTO GROUND SUBSTANCE KEEPS SKIN FIRM AND HYDRATED ● PACINIAN CORPUSCLES: RESPOND MAINLY TO CHANGE IN PRESSURE AND VIBRATION (PHONE) ● "OTHER STRUCTURES: BLOOD VESSERS, SWEAT GLANDS HAIR, SEBACEOUS GLANDS AND ALDIPOSE TISSUE MC 1 ANATOMY AND PHYSIOLOGY HYPODERMIS 1. SUBCUTANEOUS LAYER DEEP TO THE SKIN 2. COMPOSED OF ADIPOSE (FAT) AND AREOLAR CONNEC TUE TISSUE SKIN COLOR 1. THERE PIGMENTS CONTRIBUTE TO SKIN COLOR ● MELANIN YELLOW TO REDDISH-BROWN TO BLACK PIGMENT RESPONSIBLE FOR DARK SKIN COLORS ● FRECKLES AND PIOMENED HOLES RESULT FROM LOCAL ACCUMULATIONS OF MELANIN 2. CAROTENE YELLOW TO GRACE PIGMENT, MOST OBVIOUS IN THE PALMS AND SOLES OF THE FEET 3. HEMOGLOBIN-REDDISH PIGMENTS RESPONSIBLE FOR THE PINKISH HUE OF THE SKIN SWEAT GLANDS 1. SWEAT GLANDS OR PSEU DORIFEROUS GLANDS ARE SIMPLE CALLED TUBULAR GLANDS 2. THEY PRODUCE SWEAT, A WATERY MIXTURE OF SALTS ANTIBODIES AND METABOLIC WATERS 3. SWEAT PREVENTS OVERHEATING OF THE BODY AND THIS HELPS REGULATE BODY TEMPERATURE. TYPES OF SWEAT GLANDS ● ECCRINE SINEAT GLANDS - FOUND IN THE PALMS, SOLES OF THE FEET, AND FOREHEAD ● APOCRINE SWEAT GLANDS FOUND IN AXILLARY AND ANOGENITAL AREAS ● CERUMINOUS GLANDS - MODIFIED APOCRINE GLAND IN EXTERNAL EAR CANAL AND SECRET CELUMEN ● MAMMADY GLANDS - SPECIALIZED SWEAT GLANDS THAT SECRET MLK SEBACEOUS GLANDS ● SOFTEN SKIN WHEN STIMULATED BY HORMONES ● SIMPLEST ALVEOLAR GLANDS FOUND ALL OVER THE BODY ● MICROSCOPIC GLANDS FOUND IN YOUR HAIR FOLLICLES THAT SECRETE SEBUM HAIR 3 ● HELPS MAINTAIN WARMTH, ALERTS THE BODY TO PRESENCE OF INSECTS ON THE SKIN AND GUARDS THE SCALP AGAINST PHYSICAL TRAUMA, HEART LOSS AND SUNLIGHT ● FILAMENTHOUS STRAND OF DEAD KERTINIZED CELLS PRODUCED BY HAIR FOLLIATES ● CONTAINS HARD KERATIN, WHICH IS TOUGHER AND MORE DURABLE THAN THE SOFT KERATIN ON THE SKIN ● MADE UP OF THE SHAFT PROJECTING FROM THE SKIN AND THE ROOT EMBEDDED IN THE SKIN ● CONSIST OF A CORE CALLED THE MEDULLA, A CORTEX AND AN OUTERMOST CUTICLE ● HAIR - ALSO CALLED FUR (IF IT IS IN LARGE AMOUNTS) - FOUND EVERYWHERE ON THE SKIN EXCEPT ON THE PALMS SOLES, LIPS, NIPPLES, PARTS OF THE GENITALIA AND DISTAL PARTS OF THE FINGERS AND TOES A. HAIR BULB - THE "GROWTH ZONE" B. CORTEX - CENTRAL CORE COVERING. C. MEDULLA - THE "CENTRAL CORE” D. CUTICLE - THE HEAVIEST KERATINIZED REGION EACH HAIR ADVISES FROM A HAIR FOLLICLE (AN F TENSION) OF THE EPIDERMIS THAT ORIGINATES DEEP IN THE PERMIS)... THE SHAFT OF THE HAIR PROTRUDES ABOVE THE SURFACE OF THE SKIN, WHEREAS THE ROOT AND HAIR BULB ARE BELOW THE SURFACE A HAIR HAS A HARD CORTEX WHICH SURROUNDS A SOFTER CENTER CALLED THE MEDULA THE CORTEX IS COVERED BY THE CULTICLE (A SINGLE LAYER OF OVERLAPPING CELLS THAT HOLDS THE HAIR IN THE FOLLICLES) THE HAIR FOLLICLE CAN PLAY AN IMPORTANT ROLE IN SKIN REPAIR... IF THE SURFACE EPIDERMIS DAMAGED, THE EPITHELIAL CELLS WITHIN THE FOLLICLE CAN DIVIDE AND BECOME A SOURCE OF NEW CELLS. HAIR IS PRODUCED IN THE HAIR BULB, WHICH RESTS ON THE HAIR PAPILLA BLOOD VESSELS WITHIN THE PAPILLA SUPPLY THE HAIR BULB WITH THE NOURISHMENT NEEDED TO PRODUCED THE HAIR ROOT AND SHAFT CONSISTS OF COLUMNS OF MC 1 ANATOMY AND PHYSIOLOGY DEAD, KERATINIZED EPITHELIAL CELLS EYE LASHES GROW FOR ABOUT 30 DAYS AND REST FOR 105 DAYS WHEREAS SCALP HAIRS GROW FOR 3 YEARS AND REST FOR 1-2 YEARS HAIR FOLLICLE ● ROOT SHEATH EXTENDING FROM THE EPIDERMAL SURFACE INTO THE DERMIS ● DEEP END IS EXPANDED FORMING & HAIR BULB ● A KNOT OF SENSORY NERVE ENDINGS (A ROOT HAIR PLEXUS) WRAPS AROUND EACH HAIR BULB ● BENDING & HAIR STIMULATES THESE ENDINGS, HENCE OUR HAIRS ACT FAST AS SENSITIVE TOUCH RECEPTORS NAILS - MOST OF NAIL BODY APPEARS PINK HUE TO UNDERLYING CAPILLARIES - FREE DEGREE IS WHITE BECAUSE OF ABSENCE OF UNDERLYING CAPILLAPIES - LUNULA CRESCENT SHADED WRITE PORTION AT PROXIMAL END OF NAIL - PLATES OF TIGHTLY PACK, HARD, KERATINIZED EPIDERMAL CELLS - FORM A CLEAR AND SOUND COVERING OVER DORSAL SURFACES OF DISTAL PORTIONS OF DIGITS NAILS CONSISTS OF - NAIL BODY: PORTION OF NAIL THAT IS VISIBLE - FACE EDGE: PORTION THAT MAN EXTEND PAST DISTAL FIND - NAIL ROOT: PORTION BURIED IN A FOLD OF SKIN STRUCTURE OF NAILS MAJOR FUNCTION OF INTEGUMENTARY SYSTEM (PSYTE) 1. PROTECTION - THE SKIN PROVIDES PROTECTION AGAINST ABRASION AND ULTRAVIOLET LIGHT IT ALSO PREVENTS THE ENTRY OF MICROORGANISMS AND THE OCCURRENCE OF DEHYDRATION. 2. SENSATION - THE SYSTEM CONTAINS SENSORY RECEPTORS (DETECTS HEAT; COLD, TOUCH, PRESSURE AND PAIN) 3. VITAMIN D PRODUCTION - THE SKIN PRODUCES A MOLECULE THAT CAN 4 TRANSFORM INTO VITAMIN D WHEN IT IS EXPOSED PO UV LIGHT. VITAMIN D ENHANCES CALCIUM (REGULATES CALCIUM HOMEOSTASIS) 4. TEMPERATURE REGULATION - THE AMOUNT OF BLOOD FLOW BENEATH THE SKIN'S SURFACE AND THE ACTIVITY OF SWEAT GLANDS IN THE SKIN BOTH HELP REGULATE THE BODY'S TEMPERATURE A. HEAT LOSS (THROUGH VASODILATION) - THE SWEAT GLANDS ARE ACTIVATED, ALLOWING BLOOD TO FLOW INTO THE CAPILLARY BEDS B. HEAT RETENTION (THROUGH VASOCON STRICTION) - BLOOD IS NOT ALLOWED TO FLUSH INTO THE SKIN 2 INTEGUMENTARY SYSTEM CAPILLARIES HEAT - FLOOD VOLUMED BILATE IS INCREASE IN BLOOD SUPPLY COLD - BLOOD VOLUMED CONSTRICTED DECREASE IN BLOOD SUPPLY AND DISSIDATION OF HEAT EXCRETION - REMOVAL OF WASTE PRODUCTS IN THE BODY