1. Chapter 5: integumentary system

2. Structure of the skin Skin is called the cutaneous or integument
Skin has two regions
The epidermis
The dermis

3. Structure of the skin Epidermis The outer thinner region of the skin
Made up of stratified squamous epithelium
Divided into the stratum basale and the stratum corneum

4. Structure of the skin Epidermis
Stratum basale- just superior of the dermis
Langerhans cells- macrophages found deep in the epidermis that phagocytize microbes and simulate the immune system
Melanocytes- specialized cells in the deeper epidermis that produce melanin, responsible for skin color

5. Structure of the skin Epidermis
Stratum corneum- the uppermost layer of the skin
Keratin- a fibrous, waterproof cell
Mechanical barrier against microbe invasion

6. Structure of the skin
Epidermis

7. Structure of the skin Dermis A deeper and thicker region
Composed of dense irregular connective tissue
Dermal papillae causes ridges resulting in fingerprints
Contains collagenous and elastic fibers

8. Structure of the skin Dermis
Collagenous fibers prevent skin from being torn and great resistance from over stretching
Elastic fibers allow movement but maintain normal skin tension
A deeper and thiker region

9. Structure of the skin
Dermis

10. Structure of the skin Dermis
Decubitus ulcers- sore caused by a lacked of blood flow in a particular area that is restricted

11. Structure of the skin Hypodermis Subcutaneous tissue
Lies below the dermis
Composed of loose connective tissue including adipose

12. Accessory Structures Hair Found everywhere on the body except: Palms
Soles
Lips
Nipples

13. Accessory Structures
Hirsutism: excessive body and facial hair

14. Accessory Structures
Alopecia- lack of hair or baldness

15. Accessory Structures Hair follicles:
Are formed from epidermal cells
But are located in the dermis
Root- portion of the hair found in the follicle
Shaft- portion of the hair found above the skin

16. Accessory Structures Hair follicles:
Are formed from epidermal cells
But are located in the dermis
Root- portion of the hair found in the follicle
Shaft- portion of the hair found above the skin

17. Accessory Structures
Hair follicles:

18. Accessory Structures Nails:
From special epithelial cells at the base of the nail called the nail root
Nail body is the visible portion of the nail
Lunula is the whitish half moon shaped base

19. Accessory Structures
Glands: specialized cells that produce and secrete a substance into ducts

20. Accessory Structures Sweat gland: Present in all skin Tubular
Glands are active under stress

21. Accessory Structures Sweat gland: Apocrine gland
Open into hair follicles
In anal region, groin, and armpits
Begins secreting at puberty

22. Accessory Structures Sweat gland: Eccrine glands
Open to surface of the skin
Active when a person is hot
Contains water, salts, urea, and waste

23. Accessory Structures Sebaceous glands Associate with a hair follicle
Secrete sebum : an oil substance
Lubricates and waterproofs

24. Accessory Structures Acne vulgaris Most common
Inflammation of the sebaceous glands

25. Accessory Structures
Mammary glands
Located in breast
Produces milk

26. Disorders of the skin
Athlete’s Foot: fungal infection of the toes and sole

27. Disorders of the skin
Impetigo: highly contagious bacterial infection that results in pustules

28. Disorders of the skin
Psoriasis: chronic condition, the skin is reddish pink patches covered by silver scales

29. Disorders of the skin
Eczema: an inflammation of the skin caused by sensitivity

30. Disorders of the skin
Cyanosis: condition in which the skin has a bluish tint caused by insufficient oxygen in the blood

31. Disorders of the skin
Jaundice: yellowing of the skin caused by an accumulation of bilirubin

32. Disorders of the skin
Albinism: loss of pigment in the skin creating patches of white skin

33. Disorders of the skin
Freckles: melanin concentrated in local areas

34. Disorders of the skin
Dandruff: flaking of the scalp due to accelerated keratinization

35. Disorders of the skin
Uricaria: hive caused by an allergic reaction

36. Disorders of the skin Nonmelanoma: Basal cell carcinoma Most common
Caused from UV exposure
Signs are tumors, open sores, reddish patches, smooth growths, shiny bumps or pale marks

37. Disorders of the skin
Nonmelanoma: Basal cell carcinoma

38. Disorders of the skin Nonmelanoma: Squamous cell carcinoma
More like to spread
Signs bleeding warts and scabs

39. Disorders of the skin
Nonmelanoma: Squamous cell carcinoma

40. Disorders of the skin
Squamous cell carcinoma Basal cell

41. Disorders of the skin Melanoma: Starts as a mole
Skin around mole turns colors
Occurs mostly in fair skinned individuals with a history of sunburns as a child

42. Disorders of the skin
Melanoma:

43. Disorders of the skin
Moles:
due to an overgrowth of melanocyte

44. Disorders of the skin
Warts: caused by a virus

45. Disorders of the skin Burns Caused by Chemicals, Radiation, and Heat
Extent of a burn is determined by the “Rule of Nine”
Classified by depth of the burn and the extent of the burn

46. Disorders of the skin First Degree Burns Only the epidermis
Reddness and pain,
no blisters
Subside in 2-3 days

47. Disorders of the skin Second Degree Burns
Only the epidermis and dermis
Reddness , pain, and blisters
Subside in days

48. Disorders of the skin Third Degree Burns
Destroys entire thickness of the skin
Leathery surface of brown, black, tan, white or red
Destroyed nerves, blood vessels, glands, and follicles

49. Disorders of the skin
Third Degree Burns

50. Disorders of the skin Fourth Degree Burns Destroyed down to bone
Limited chance of survival

51. Disorders of the skin Major concerns with burns: Fluid loss Heat loss
Bacterial infections

52. Disorders of the skin Autografting Heterografting
Graft taken from another part of the patients body
Preferred method
Heterografting
Graft taken from another person

53. Disorders of the skin
Skin Grafts

54. Effects of aging Epidermis
Maintain thickness but cell turnover decreases
Skin is looser

55. Effects of aging Dermis Thinner Flattened
Collagenous fibers coarser, thicker, far apart
Upper layer lost
Decrease in melanocytes

56. Effects of aging
Hypodermis
Adipose tissue decreases

57. Effects of aging Wrinkles caused by: Loose epidermis
Fibers are fewer and disorganized
Less padding

58. Homeostasis Functions of the skin Protective function
Helps regulate water loss
Produces vitamin
Regulates body temperature
Gathers sensory information

59. Homeostasis Hypothermia: Body temperature below normal
Characterized by
Uncontrolled shivering
Incoherent speech
Lack of coordination
Progresses to
pulse rate slows
hallucinations
shallow breathing
rigidity

60. Homeostasis Hyperthermia: Body temperature above normal
Heat stroke- body temperature above 110 degrees F w/o sweating
Fever