1. Classification of Body Membranes
Epithelial membranes—composed of epithelial tissue and an underlying layer of connective tissue
Connective tissue membranes—composed largely of various types of connective tissue

2. Classification of Body Membranes
Epithelial membranes
Cutaneous membrane—the skin
Serous membranes—simple squamous epithelium on a connective tissue basement membrane
Types
Parietal—line walls of body cavities
Visceral—cover organs found in body cavities

3. Serous Membranes, cont Pleura- thoracic cavity
Peritoneum- abdominal cavity
Serous membranes secrete thin, watery fluid that helps reduce friction

4. Pleurisy
inflammation of the pleura that line the chest walls and cover the lungs
Pain is caused by friction of the lungs rubbing against the chest walls

5. Periotonitis
Inflammation of the serous membranes in the abdominal cavity

6. Mucous Membranes Line body surfaces opening directly to the exterior
Respiratory
Digestive
Urinary
Reproduction
Produce mucous to keep membranes moist and soft

7. Mucocutaneous Junction
The point where skin and mucous membranes meet
Lack hair or sweat glands that characterize skin
Can be common sites for infection
Examples:
Eyelids
Nasal openings
Vulva
anus

8. Classification of Body Membranes
Connective tissue membranes
Do not contain epithelial components
Produce a thick, colorless lubricant called synovial fluid
line spaces between bones and joints
Also line bursae- small, cushion-like sacs found between moving body parts

9. The Skin Structure—two primary layers called epidermis and dermis
Outermost and thinnest primary layer of skin
Composed of several layers of stratified squamous epithelium
Stratum germinativum—innermost layer of cells that continually reproduce, and new cells move toward the surface

10. The Skin
Epidermis
As cells approach surface, they are filled with a tough, waterproof protein called keratin and eventually flake off
Stratum corneum—outermost layer of keratin-filled cells

11. The Skin
Epidermis
Pigment-containing layer—epidermal layer that contains pigment cells called melanocytes, which produce the brown pigment melanin

12. Melanin What gives color to the skin
Melanocytes- pigment producting cells
Skin color genes are inherited
Other factors that effect skin color
Cyanosis- bluish gray- decreased bloodflow
Vitiligo- patchy looking areas of light skin- due to loss of melanocytes
Albinism- partial or total lack of melanin pigment in the skin

14. Variations of skin pigment continued
Freckles
Most occur due to a genetic trait in light skinned people
chronically in sun exposed areas

15. Blisters Cells of the epidermis are packed tightly together
When these links are weakened or destroyed due to burns, friction, or irritants blisters form
Blisters can also occur at the Dermal- epidermal junction- area of contact between the two that “glues” them together

16. The Skin
Dermis
Deeper and thicker of the two primary skin layers and composed largely of connective tissue
Upper area of dermis characterized by parallel rows of peg-like dermal papillae
Ridges and grooves in dermis form pattern unique to each individual (basis of fingerprinting)
Deeper areas of dermis filled with network of tough collagenous and stretchable elastic fibers

17. Striae- are stretch marks
Occur when the connective and elastic tissues are stretched beyond their ability to rebound
Wrinkles occur because the amount of elastic fibers in the dermis decrease, and the amount of fat in the subcutaneous tissue is reduced
                                                             

18. The Skin
Dermis
Dermis also contains nerve endings, muscle fibers, hair follicles, sweat and sebaceous glands, and many blood vessels

19. Problems with development of the dermis blood vessels can cause birthmarks
Strawberry hemangioma
Port-wine stain
“stork bite”

20. Nails Nail body is the visible part of the nail
Produced by epidermal cells over terminal ends of fingers and toes
Nail body is the visible part of the nail
Nail Root is the rest of the nail that in a groove and is hidden by the cuticle

21. Lunula “little moon” is the nail body closest to the root; crescent shaped white area
Nail Bed is the layer of epithelium under the nail. Because it has a large blood supply it appears pink under a clear nail
If blood oxygen levels drop the nail bed appears blue

22. Age and race can influence normal shape and appearance of nails
Light skinned- longitudinal lines
Dark skin- pigmented bands
Onycholysis “nail pitting” separation of nail from nail bed starting at the distal end; common in patients with psoriasis

23. The Skin Appendages of the skin Hair
Soft hair of fetus and newborn called lanugo
Hair growth requires epidermal tube-like structure called hair follicle
Hair growth begins from hair papilla

24. Hair Follicle- small tube located in the dermis where hair growth begins
Papilla- cluster of cells at the base of the follicle
“hair root” is hidden in follicle
“shaft” is the visible part of the hair
As long as the cells in the papilla are alive new hair will grow to replace plucked or cut hair
Cutting or shaving hair DOES NOT make it grow faster or become coarser because neither effects the cells in the papilla

25. Alopecia (hair loss) Male pattern baldness Hereditary Result of aging
Alopecia areata
Last 1-3 months
Round or oval sudden hair loss
Chemotherapy
Radiation
Extreme stress
Certain metabolic or endocrine diseases
Reaction to certain drugs
Postpardum alopecia
1-4 months post giving birth
Front and sides of scalp
<one year
Alopecia totalis
Complete loss of scalp hair with no apparent reason
May experience periods of re- growth and then loss again

26. Goose Bumps Arrector pili muscle
Attached to the base of the papilla and to the side of the hair follicle
Involuntary muscle contraction; usually when we are frightened or cold

27. The Skin Appendages of the skin Receptors
Specialized nerve endings—make it possible for skin to act as a sense organ
Meissner’s corpuscle—capable of detecting light touch
Pacinian corpuscle—capable of detecting pressure

28. The Skin
Skin glands
Types
Sweat or sudoriferous
Sebaceous

29. Sweat (sudoriferous) glands
Two types
Eccrine
More numerous
Cover most of body surface
Secrete transparent, watery liquid
1 inch of skin contain approx. 3000!
Produce perspiration or sweat, which flows out through pores on skin surface
Function throughout life and assist in body heat regulation
Apocrine
Found primarily in the axilla and pigmented skin around the genitals
Thicker, milky secretions
Odor is caused by the secretion mixing with bacteria on the skin, not the secretion itself
Enlarge and begin to function at puberty

30. Sebaceous gland Secrete oil or sebum for hair and skin
Level of secretion increases during adolescence
Amount of secretion regulated by sex hormones
Acne vulgaris inflammation of sebaceous gland ducts
Grow where hair grows, have ducts that open into the hair follicles
Often sebum accumulates in the ducts forming white pimples or darkens and forms blackheads
Secretions decrease with age which contributes to wrinkles and cracking of skin

31. Functions of the Skin Protection—first line of defense
Against infection by microbes
Against ultraviolet rays from sun
Against harmful chemicals
Against cuts and tears
Skin grafts

32. Functions of the Skin Temperature regulation
Skin can release almost 3000 calories of body heat per day
Mechanisms of temperature regulation
Regulation of sweat secretion
Regulation of flow of blood close to the body surface

33. Functions of the Skin Sense organ activity
Skin functions as an enormous sense organ
Receptors serve as receivers for the body, keeping it informed of changes in its environment—disorders of the skin (dermatomes)

34. Subcutaneous Injections
Carries major blood vessels and nerves
Spongy texture
Allows for rapid, relatively pain-free absorption
Liquid medicine and pelleted implant materials

35. Disorders of the Skin

36. Acne Acne vulgaris Most common kind Occurs mostly in adolescents
Caused by increased sebum production between ages
Papules are inflammed lesions
Pustules are pus filled pimples that rupture
Treatment
Proper cleaning
Topical medications
Oral antibiotics and other drugs

37. ATHLETE’S FOOT
Contagious fungal infection
Usually contracted in public baths and showers
Rx – antifungal agents

38. Skin Lesions Elevated lesions -cast a shadow outside their edges
Papule—small, firm raised lesion
Plaque—large raised lesion
Vesicle—blister
Pustule—pus-filled lesion
Crust—scab
Wheal (hive)—raised, firm lesion with a light center

39. Flat lesions —do not cast a shadow
Skin Lesions
Flat lesions —do not cast a shadow
Macule—flat, discolored region
Ex. Freckle
Copyright © 2005, 2002, 1997, 1992 by Mosby, Inc. All rights reserved.

40. Copyright © 2005, 2002, 1997, 1992 by Mosby, Inc. All rights reserved.
Skin Lesions
Depressed lesions cast a shadow within their edges
Excoriation—missing epidermis, as in a scratch wound
Ulcer—craterlike lesion
Fissure—deep crack or break
Copyright © 2005, 2002, 1997, 1992 by Mosby, Inc. All rights reserved.

41. DERMATITIS
Non-specific inflammation of skin
Can be rash – reaction to soap,
plants, etc.
Can be emotional – stress can
cause skin blotches

42. SKIN CANCER
Associated with exposure to sun (UV rays)
Most common type of cancer in people

43. Skin Cancer Three common types
Squamous cell carcinoma—the most common type, characterized by hard, raised tumors
Basal cell carcinoma—characterized by papules with a central crater; rarely spreads
Melanoma—malignancy in a nevus (mole); the most serious type

44. MALIGNANT MELANOMA
Occurs in melanocytes
Metastasizes to other areas quickly
Appears as brown or black irregular patch that occurs suddenly
A change in an existing wart or mole may indicate melanoma
Rx – surgical removal of melanoma and surrounding area and chemotherapy

45. GENITAL HERPES
Viral
Blister in genital area
Spread through sexual contact
Periods of remission and exacerbation
Rx – Acyclovir
Can be passed to newborn during vaginal delivery

46. BURNS
Caused by radiation, sun, boiling water, chemicals, fire or electricity
RULE OF NINES – Measures percent of body burned. Body divided into 11 area, each is 9% of body surface.

47. BURNS FIRST DEGREE Superficial Skin red and dry
Involves only epidermis
Rx – cold water

48. BURNS SECOND DEGREE Epidermis and dermis
Pain, swelling, redness and blistering
Skin may be exposed to infection
Rx – pain medication, dry sterile dressing

49. Burns
Third-degree (full-thickness) burns characterized by complete destruction of the epidermis and dermis
May involve underlying muscle and bone (fourth-degree)
Lesion is insensitive to pain because of destruction of nerve endings immediately after injury—intense pain is soon experienced
Symptoms – loss of skin, blackened skin
May be life threatening

50. RULE OF NINES
The volume of fluid lost can be estimated indirectly by determining how much of the body surface is burned (extent of burns), using the rule of nines.
Body divided into 11 areas of 9% each
Additional 1% of body surface area around genitals

51. Copyright © 2005, 2002, 1997, 1992 by Mosby, Inc. All rights reserved.
Skin Infections
-Impetigo—highly contagious staphylococcal infection
Tinea—fungal infection (mycosis) of the skin;
Boils—furuncles; staphylococcal infection in hair follicles
Scabies—parasitic infection
Copyright © 2005, 2002, 1997, 1992 by Mosby, Inc. All rights reserved.

52. Vascular and Inflammatory Skin Disorders
Decubitus ulcers
Urticaria or hives
Scleroderma
Psoriasis
Eczema
Copyright © 2005, 2002, 1997, 1992 by Mosby, Inc. All rights reserved.