Ch. 4 Skin and Body Membranes

Transcription

1 Ch. 4 Skin and Body Membranes Title: Oct 20 7:35 AM (1 of 69)

2 Essential Question: How is skin considered a body system? Title: Oct 20 7:41 AM (2 of 69)

3 Body membranes: cover surfaces line body cavities protective sheets around organs 2 types: epithelial connective Title: Oct 20 7:43 AM (3 of 69)

4 Epithelial Membranes: (do have connective tissue underneath) Cutaneous = skin keratinizing stratified squamous epithelium underlying dermis = dense fibrous connective tissue dry membrane Title: Oct 20 7:48 AM (4 of 69)

5 Mucous Membranes (mucosa): epithelium on loose connective tissue called lamina propia lines all body cavities open to exterior respiratory, digestive, urinary, reproductive cell make up varies stratified squamous mouth, esophagus simple columnar digestive tract wet membranes adapted for absorption, secretion Title: Oct 20 7:59 AM (5 of 69)

6 Title: Oct 20 8:27 AM (6 of 69)

7 Serous membranes (serosa): simple squamous epithelium on aerolar tissue line body cavities closed to exterior occur in pairs parietal lines wall of ventral cavity visceral covers outside of organs between layers = serous fluid secreted by the membranes (prevents friction) Title: Oct 20 8:03 AM (7 of 69)

8 Title: Oct 20 8:28 AM (8 of 69)

9 Serous membrane names depending on where found: peritoneum abdominal cavity pleura lungs pericardium heart Title: Oct 20 8:28 AM (9 of 69)

10 Synovial membranes: soft aerolar tissue, no epithelium line fibrous capsules surrounding joints secrete lubricating fluid line bursae (small sacs) and tendon sheaths (tubelike) cushion during muscle activity Title: Oct 20 8:31 AM (10 of 69)

11 Title: Oct 20 8:31 AM (11 of 69)

12 Skin aka: integumentary system (What kind of membrane?) Title: Oct 20 8:30 AM (12 of 69)

13 Functions: Protection mechanical damage chemical damage bacterial damage ultraviolet damage thermal damage desiccation (drying out) Title: Oct 20 8:31 AM (13 of 69)

14 heat maintenance to lose heat activates sweat glands to retain heat capillaries constrict goosebumps arrector pili makes hair stand up to try and trap heat subcutaneous layer = fat = insulation Title: Oct 20 8:39 AM (14 of 69)

15 Excretion lose urea and uric acid via sweat glands synthesis of Vitamin D modified cholesterol molecules converted to vitamin D by sunlight Title: Oct 20 8:42 AM (15 of 69)

16 other functions: nervous system receptors found here pain temperature pressure light touch Title: Oct 20 8:44 AM (16 of 69)

17 Structure: Epidermis top layers Dermis bottom layers subcutaneous fat Title: Oct 20 8:46 AM (17 of 69)

18 Epidermis: stratified squamous epithelium keratinizing 5 zone layers = strata avascular cells = keratinocytes = produce keratin Title: Oct 20 8:49 AM (18 of 69)

19 Layers from the inside out (deep to superficial): Stratum Basale aka. stratum germinativum actively mitotic (dividing), millions daily daughter cells pushed upwards close to dermis only epidermal cells that receive nourishment melanocytes found here produce melanin = color of skin sun exposure= more melanin production cells phagocytize the pigment, protects DNA freckles, moles = concentrated areas of melanin Title: Oct 20 8:48 AM (19 of 69)

20 Title: Oct 20 12:01 PM (20 of 69)

21 albinism= lack of melanin pigment missing enzyme that changes tyrosine into melanin genetic problem Vitilago skin condition that causes loss of pigment in skin melanocytes are destroyed 2 4 million Americans cause unknown, but may be genetic, immunological or neurological Title: Oct 20 11:39 AM (21 of 69)

22 Stratum Spinosum = "spiny layer" 8 10 layers thick irregular shaped cells cells in this layer starts synthesis of keratin, lots of RNA present Title: Oct 20 11:46 AM (22 of 69)

23 Title: Oct 20 12:02 PM (23 of 69)

24 Stratum granulosum granular layer keritinization happens here cell replaces cytoplasm with keratin (protein) waterproofs the cell 3 5 layers thick top layer, cells start to die lysosomes release digestive enzymes Title: Oct 20 11:49 AM (24 of 69)

25 Title: Oct 20 12:02 PM (25 of 69)

26 Stratum Lucidum clear layer 3 5 layers thick lose this layer as we age found in soles of feet, palms of hands made of dead cells Title: Oct 20 11:52 AM (26 of 69)

27 Title: Oct 20 12:02 PM (27 of 69)

28 Stratum Corneum outermost layer of skin layers thick stratified squamous keratinizing epithelial dead cells, no nutrients shed skin every days hyperkeratosis = callous cause = friction Title: Oct 20 11:54 AM (28 of 69)

29 Title: Oct 20 12:00 PM (29 of 69)

30 Layers of Dermis: Papillary Layer upper dermal region dermal papillae make the ridges for your fingerprints, genetic contains capillaries nutrients house pain receptors = Meissner's corpuscles made of dense fibrous connective tissue Title: Oct 20 12:03 PM (30 of 69)

31 Reticular layer makes up 80% of dermis made of collagen and elastin fibers contain blood vessels nutrients, temp. regulation sweat and oil glands located here nerves located here pressure receptors Pacinian corpuscles phagocytes here kill bacteria Title: Oct 20 12:09 PM (31 of 69)

32 Hematoma = bruise capillaries break and bleed into surrounding tissue Title: Oct 20 12:13 PM (32 of 69)

33 Decubitis ulcer = bed sore weight of body puts pressure on skin over bones restricts blood supply, cells die, small cracks form Title: Oct 20 12:19 PM (33 of 69)

34 Stretch marks breaking apart of dense tissue scar like cause rapid weight gain, pregnancy Title: Oct 20 12:23 PM (34 of 69)

35 blisters separation of epidermis from dermis burn blister close up.html causes: friction, heat, chemicals Title: Oct 20 12:28 PM (35 of 69)

36 underneath dermis = subcutaneous tissue = Fat adipose tissue insulation protection Title: Oct 20 12:32 PM (36 of 69)

37 Skin color melanin brownish pigment epidermis carotene orange pigment carrots stratum corneum, subcutaneous tissue hemoglobin pink color emotions heat Title: Oct 20 12:41 PM (37 of 69)

38 Skin disorders that affect skin color cyanosis lack of oxygen to skin turns blue ex. emphysema jaundice yellow color to skin indicates a liver problem bilirubin pigments released by liver and colors skin, normally get broken down Title: Oct 20 12:48 PM (38 of 69)

39 pallor lack of blood (hemoglobin) cause anemia, scared, before passing out bronzing metallic sheen cause hypofunction of adrenal cortex erythema redness due to emotional stimuli, fever, allergies Title: Oct 20 12:52 PM (39 of 69)

40 Skin appendages: Glands exocrine made from stratum basale 1. sebaceous glands = oil glands Title: Oct 20 12:56 PM (40 of 69)

41 all over skin, except palms and soles ducts empty into hair follicle, some to surface sebum = oily substance and fragmented cells lubricant has chemicals that kill bacteria become very active during puberty male sex hormones Title: Oct 20 12:58 PM (41 of 69)

42 whitehead = pimple blocked sebaceous gland blackhead = whitehead that has oxidized acne = infection of sebaceous glands Title: Oct 20 1:02 PM (42 of 69)

43 seborrhea= "cradle cap" cause overactive sebaceous glands in infants Title: Oct 20 1:05 PM (43 of 69)

44 2. sweat glands = sudoriferous glands A. eccrine glands produce sweat (water, salts, vit C, metabolic wastes urea, ammonia, lactic acid ph = 4 6 inhibits bacterial growth pores regulate body temp secrete sweat if high body temp hot day lose up to 7 liters of water Title: Oct 20 1:11 PM (44 of 69)

45 B. Apocrine sweat glands associated wtih axillary and genital areas larger than eccrine glands ducts empty into hair follicles secrete fatty acids and proteins, water, salts, etc. (odorless) milky to yellowish color bacteria on skin use secretions for nutrients causes odor (BO) begin functioning at puberty due to androgens (male hormones) no heat regulation Title: Oct 20 3:10 PM (45 of 69)

46 Hair function: guard head against bumps shields eyes keep debris out of respiratory passages evolution insulation Title: Oct 20 3:14 PM (46 of 69)

47 hair follicle flexible structure root part in follicle shaft part projecting from scalp formed by stratum basale Title: Oct 20 3:17 PM (47 of 69)

48 hair made in inferior follicle, pushes out and dies Title: Oct 20 3:20 PM (48 of 69)

49 hair has three parts: medulla cortex pigmented cuticle scale like Title: Oct 20 3:24 PM (49 of 69)

50 follicle epidermal sheath forms hair dermal sheath supplies blood reinforces arrector pili muscle pulls hair upright Title: Oct 20 3:23 PM (50 of 69)

51 Nail = scale like modification of epidermis free edge, body, root (under skin), nail folds, cuticle Title: Oct 20 3:28 PM (51 of 69)

52 nail bed under nail, stratum basale here nail matrix where nail growth occurs keratinized Title: Oct 20 3:30 PM (52 of 69)

53 Lunula = white crescent of nail Title: Oct 20 3:32 PM (53 of 69)

54 Skin Imbalances 1. Athlete's foot (tinea pedis) fungal infection cure.com/ Title: Oct 20 3:33 PM (54 of 69)

55 2. Boils and Carbuncles inflammation of hair follicles and sebaceous glands carbuncles = many boils together, Staphylococcus aureus Title: Oct 20 3:35 PM (55 of 69)

56 3. cold sores (fever blisters) cause herpes simplex in nerve activated by emotions, fever, UV light usually on lips, mouth Title: Oct 20 3:39 PM (56 of 69)

57 4. contact dermatitis cause exposure to chemicals, ex. poison ivy allergic response contact dermatitis/1133 Dermatitis contact/ Title: Oct 20 3:42 PM (57 of 69)

58 5. impetigo pink, water filled lesions, develop yellow crust cause Staphylococcus infection common in elementary school children imgs.html Title: Oct 20 3:44 PM (58 of 69)

59 6. Psoriasis chronic condition reddened epidermal lesions, with dry silvery scales unknown cause, may be genetic Title: Oct 20 3:47 PM (59 of 69)

60 Burns = tissue damage and death due to intense heat, electricity, UV radiation & chemicals Immediate life threatening problems: dehydration wound seeps liquids infection pathogens bacteria & fungi burned skin is sterile for 24 hours leading cause of death in burn victims Title: Oct 20 3:50 PM (60 of 69)

61 To determine how much of body is burned: The Rule of the Nines Title: Oct 20 3:54 PM (61 of 69)

62 Title: Oct 20 3:55 PM (62 of 69)

63 Classification of Burns: 1st degree only epidermis damaged red & swollen not serious, heal in 2 3 days ex. mild sunburn partial thickness burn Title: Oct 20 3:57 PM (63 of 69)

64 2nd degree burn injury to epidermis and upper region of dermis red and painful blisters appear (separation of epidermis from dermis) regeneration of tissue, no scars if not infected partial thickness burn Title: Oct 20 4:02 PM (64 of 69)

65 3rd degree burn entire thickness of skin burned full thickness burn can be down to bone appears gray white or black nerve endings destroyed not painful initially no regeneration, need skin grafting Title: Oct 20 4:02 PM (65 of 69)

66 skin graft Title: Oct 20 4:09 PM (66 of 69)

67 1st degree 2nd degree 3rd degree Title: Oct 20 4:02 PM (67 of 69)

68 Burns considered critical if: 1. over 25 % of body with 2nd degree burns 2. Over 10% of body with 3rd degree burns 3. 3rd degree burns on face, hands or feet. Title: Oct 20 4:10 PM (68 of 69)

69 Title: Oct 27 3:22 PM (69 of 69)