1. Membranes and Skin

2. Function of body membranes
4.1.1 List the general function of each membrane type and give its location in the body.
4.1.2 Compare the structure (tissue makeup) of the major membrane types.
Function of body membranes
Line or cover body surfaces
Protect body surfaces
Lubricate body surfaces
Slide 4.1
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

3. Classification of Body Membranes
4.1.1 List the general function of each membrane type and give its location in the body.
4.1.2 Compare the structure (tissue makeup) of the major membrane types.
Classification of Body Membranes
Epithelial membranes
Cutaneous membrane
Mucous membrane
Serous membrane
Connective tissue membranes
Slide 4.2
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

4. Epithelial Membranes - covering and lining membranes
4.1.1 List the general function of each membrane type and give its location in the body Compare the structure (tissue makeup) of the major membrane types.
Epithelial Membranes - covering and lining membranes
Cutaneous membrane – Skin (Integument)
Keratinized stratified squamous epithelium
Dense fibrous connective tissue
Exposed to air so it is a DRY membrane

5. Mucous Membranes – lines all body cavities that open to the exterior
4.1.1 List the general function of each membrane type and give its location in the body Compare the structure (tissue makeup) of the major membrane types.
Mucous Membranes – lines all body cavities that open to the exterior
Epithelium (stratified squamous, simple columnar)
Loose connective tissue (lamina propria)
WET membranes – continuously bathed in secretions (usually mucus, but not always)

6. Serous Membranes – line body cavities that do not open to the exterior
4.1.1 List the general function of each membrane type and give its location in the body Compare the structure (tissue makeup) of the major membrane types.
Serous Membranes – line body cavities that do not open to the exterior
Simple squamous epithelium
Areolar connective tissue (thin layer)
Parietal layer lines the wall of the ventral body cavity
Visceral layer lines the outside of the organs

7. Layers are separated by serous fluid (reduces friction)
4.1.1 List the general function of each membrane type and give its location in the body Compare the structure (tissue makeup) of the major membrane types.
Layers are separated by serous fluid (reduces friction)
Names depend upon locations
Peritoneum – lines the abdominal cavity
Pleura – surrounds the lungs
Pericardium – surrounds the heart

8. Connective Tissue Membranes
4.1.1 List the general function of each membrane type and give its location in the body Compare the structure (tissue makeup) of the major membrane types.
Connective Tissue Membranes
Synovial Membranes – line the fibrous capsule surrounding joints
Soft areolar connective tissue (no epithelium)
Provide a smooth surface
Secrete lubricating fluid

9. Integumentary System Consist of Cutaneous membrane (skin) Derivatives
Sweat and oil glands
Hair
Nails

10. 4.3.1 List several important functions of the integumentary system and explain how these functions are accomplished.
Funtions
Protection from mechanical and chemical damage, thermal damage, bacterial invasion, UV radiation, dessication
Aids in heat loss or retention
Aids in excretion of urea
Synthesizes Vitamin D
*Please see the chart on pg 95 for details

11. Epidermis – the outer layer
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
Epidermis – the outer layer
Stratified squamous epthelium
Keratinized – gets hard and tough
Dermis - deep to the epidermis
Made of dense connective tissue
Collagen and elastic fibers
Subcutaneous tissue or Hypodermis
Deep to the dermis (not part of skin)
Adipose tissue – anchors skin to rest of body
Shock absorber/insulator/curves

14. Composed of 5 layers called strata
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
Composed of 5 layers called strata
*from the inside going out*
Stratum basale
Stratum spinosum
Stratum granulosum
Stratum lucidum
Stratum corneum
The epidermis is avascular – has no blood supply

16. Lies closest to the dermis
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
Stratum Basale
Lies closest to the dermis
Cells receive nourishment via diffusion from the dermis
Keratinocytes are constantly dividing
Also called stratum germinativum
Daughter cells are pushed upwards to become part of the upper epidermal layers
Contains the melanocytes

17. Stratum Spinosum and Stratum Granulosum
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
Stratum Spinosum and Stratum Granulosum
Stratum Spinosum – 8 to 10 cell layers thick
Stratum Granulosum – 2 to 5 cell layers thick
Cells begin to flatten as they are pushed upwards
Increasingly fills with keratin (keratinized)
As the cell continues to push upwards, the nucleus and organelles degenerate and the cell dies

18. 4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
Stratum Lucidum – several layers of dead cells that look transparent – only occurs where skin is hairless (hands and feet)
Too much keratin
not enough nutrition or oxygen/to far from blood

19. Keratin – an exceptionally tough protein
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
Stratum Corneum – 25 or more cell layers thick, containing soft keratin.
Shingle like layers filled with keratin – cornified or horney cells
Cells are continually shed as clothes rub against your body or when you wash.
Completely new epidermis every 25 – 45 days
Keratin – an exceptionally tough protein

20. Dense fibrous connective tissue Two major regions
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
This is your “hide”
Leather = dermis
Dense fibrous connective tissue
Two major regions
Papillary layer
Reticular areas
Varies in thickness
Ex. Hands vs. eyelids

21. Dense fibrous connective tissue
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
Dense fibrous connective tissue
Papillary region
Upper area that contains the dermal papillae (fingerprints)
contains capillaries, free nerve endings, Meissner’s corpuscles (touch)
Reticular region
Lower area that contains blood vessels, sweat and oil glands, and Pacinian corpuscles (pressure)

22. Overall dermis structure
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor parts Name the layers of the epidermis and describe the characteristics of each
Overall dermis structure
Collagen and elastic fibers located throughout the dermis
Collagen fibers give skin its toughness
Collagen fibers help keep skin hydrated
Elastic fibers give skin elasticity
As we age we loose collagen/elastic fibers and subcutaneous tissue making us saggy
Blood vessels play a role in body temperature regulation

23. Three pigments contribute to skin color
4.3.3 Name the factors that determine skin color and describe the function of melanin.
Three pigments contribute to skin color
Melanin (yellow, reddish brown, black) in the epidermis
Carotene deposited in the stratum corneum and subcutaneous tissue
Hemoglobin in the dermal blood vessels

25. Melanin – FYI(steps of tanning)
Produced by cells called melanocites located in the stratum basale layer of the epidermis.
Sunlight stimulates the production of melanin.
Stratum basale cells phagocytize(eat) the pigment
Melanin forms protective layer over the sunny side of nuclei.
Freckles and moles are spots of concentrated melanin.

26. Other Influences on Skin Color
Erythema – redness
embarassment, fever, hypertension, inflammation or allergy
Palor - paleness or blanching
Fear, anger, anemia, hypotension

27. Other Influences on Skin Color (con’t)
Jaundice – yellowing
Signifies a liver disorder
Excess bile pigments are absorbed and deposited in body tissues
Bruises - hematomas
Sites where blood has escaped from the circulation and then clotted in the tissue space.
Possibly signifies a Vitamin C deficiency or hemophilia

28. Hair and hair follicles Nails
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Appendages of skin
Cutaneous glands
Oil glands
Sweat glands
Eccrine
Apocrine
Hair and hair follicles
Nails

30. 4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Cutaneous Glands
Exocrine glands that release their secretions to the outside of the body
Formed by the cells of the stratum basale but reside almost entirely in the dermis
Sebaceuos glands (oil)
Sweat glands
*exocrine glands release to a specific site.

31. Found all over the body except on palms of hands and soles of feet
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Sebaceous Glands
Produce oil
Sebum – mix of oil and cell fragments
lubricates skin and hair
kills bacteria
Found all over the body except on palms of hands and soles of feet
Ducts usually empty into a hair follicle

32. If blocked by sebum, whitehead forms
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Sebaceous Glands
If blocked by sebum, whitehead forms
If material oxidizes and dries, blackhead is formed
Acne is an active infection of the sebaceous glands

33. Sweat Glands Sudoriferous glands Two types 2.5 million per person
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Sweat Glands
Sudoriferous glands
2.5 million per person
Two types
Eccrine (ek’ rin) – more numerous – found all over the body.
Apocrine (ap’ o-krin) – found in the axillary and genital areas

34. Helps regulate body temperature
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Eccrine Sweat Glands
Found all over the body
Produce sweat – made of water, salts, vitamin C, and traces of metabolic wastes like urea, and ammonia.
Acidic (inhibits bacterial growth)
Exits the skin at sweat pores
Helps regulate body temperature

35. Found in the axillary and genital areas Larger than eccrine glands
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Apocrine Sweat Glands
Found in the axillary and genital areas
Larger than eccrine glands
Ducts empty into hair follicles
Made of same substances as eccrine sweat plus fatty acids and proteins
Bacteria live on these nutrients and cause the unpleasant BO
Function almost continuously

36. 4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Ceruminous Glands
Ceruminous glands: modified eccrine sweat glands, found on the external auditory meatus.
Earwax (cerumen). Composed of a combination of sebum and secretion from ceruminous gland.
Function- In combination with hairs, prevent dirt and insects from entry. Also keeps eardrum supple.

38. Hair and Hair Follicles Protects head from bumps
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Hair and Hair Follicles
Protects head from bumps
Shields the eyes (eyelashes)
Keeps foreign particles out of lungs
Used to provide insulation – we wear clothes now

40. Found almost everywhere on human body
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Hair
Found almost everywhere on human body
Shaft protrudes above skin surface
Root located below surface; base of root is the hair bulb
3 main regions
Actual hair shaft
Hair follicle
Hair bulb

41. Has 3 concentric layers Medulla: Central axis
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Has 3 concentric layers
Medulla: Central axis
Cortex: Forms bulk of hair
Cuticle: Forms hair surface

42. Inner - Epithelial sheath with internal and external parts.
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Hair Follicle
Outer - Dermal sheath: part of dermis that surrounds the epithelial sheath
Dermal Connective tissue, supplies blood to matrix in hair bulb
Inner - Epithelial sheath with internal and external parts.
Forms the hair
Internal part contains stratum basale that may remain after injury and supply a source of new epidermis
When hairs are pulled out, internal part comes out and is visible as white bulb

44. Fig. 5.6c

45. Internal matrix is source of hair
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Hair Bulb
Internal matrix is source of hair
Formed by division of well-nourished stratum basale epithelial cells
Daughters cells are pushed away and keratinize and die.
Contains melanocytes
Dermis projects into bulb and is blood supply

46. 4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Hair Color. Caused by varying amounts and types of melanin. Melanin can be black-brown and red.
Muscles. Arrector pili.
Type of smooth muscle.
Muscle contraction causes hair to “stand on end”
Skin pushed up by movement of hair follicle
Goosebumps

47. Cycles - Growth and resting stages
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat glands, and hair.
Hair Growth
Cycles - Growth and resting stages
Growth: cells added at base and hair elongates. Average rate is 0.3 mm/day
Rest: follicle shortens and holds hair in place. Then hair falls out of follicle. New hair begins.
Regular hair loss means hair is being replaced.
Permanent hair loss: pattern baldness most common cause

48. Nails Protect the ends of the digits
Aid in the grasping of small objects
Good for scratching
Rich blood supply
Transparent

49. Nail structures Free edge Body – visible attached portion
Root – embedded in the skin
Nail fold – skin folds that over the borders of the nail

50. Nail structures Cuticle – thick proximal nail fold
Nail bed – stratum basale of the epidermis that extends beneath the nail
Nail Matrix – thickened proximal area
responsible for growth
As cells are produced they become heavily keratinized and die

53. Leads to dehydration and electrolyte imbalance
4.4.1 Differentiate between first, second, and third degree burns Explain the importance of the “rule of nines.”
Burns
Tissue damage and cell death caused by intense heat, electricity, UV radiation or chemicals
Leads to dehydration and electrolyte imbalance
Can lead to shock – low blood volume

54. 4. 4. 1 Differentiate between first, second, and third degree burns. 4
4.4.1 Differentiate between first, second, and third degree burns Explain the importance of the “rule of nines.”
Rule of Nines
Estimate of the amount of fluids lost based on the total body surface burned.
Body is divided into 11 areas each representing 9% of the total body surface area (11 x 9 = 99) and one area the perineum makes up the remaining 1%

55. Infection is the leading cause of death in burn victims
4.4.1 Differentiate between first, second, and third degree burns Explain the importance of the “rule of nines.”
Burn Victims
Infection is the leading cause of death in burn victims
Pathogens easily invade the burned areas and multiply rapidly (lots of food)
Immune system becomes depressed

56. Damage only the epidermis Area becomes red and swollen
4.4.1 Differentiate between first, second, and third degree burns Explain the importance of the “rule of nines.”
First-Degree
Damage only the epidermis
Area becomes red and swollen
Heals in one to two days
Sunburn

57. Involves injury to the epidermis and the upper region of the dermis
4.4.1 Differentiate between first, second, and third degree burns Explain the importance of the “rule of nines.”
Second-Degree
Involves injury to the epidermis and the upper region of the dermis
Area becomes red and painful and blisters appear.
Sufficient epithelial cells are still present so regeneration will occur
Usually no scarring

58. Appears gray-white or blackened
4.4.1 Differentiate between first, second, and third degree burns Explain the importance of the “rule of nines.”
Third-Degree
Destroys the entire thickness of the skin (epidermis and all of the dermis)
Appears gray-white or blackened
Burned area is not painful because the nerve endings are destroyed
Regeneration is NOT possible – skin grafting is done

59. Burns are Critical when: Over 25% of the body has second-degree burns
4.4.1 Differentiate between first, second, and third degree burns Explain the importance of the “rule of nines.”
Burns are Critical when:
Over 25% of the body has second-degree burns
Over 10% of the body has third-degree burns
Third-degree burns on the face, hands or feet

60. Squamous Cell Carcinoma Malignant Melanoma
4.4.3 Summarize the characteristics of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.
Skin Cancer
Basal Cell Carcinoma
Squamous Cell Carcinoma
Malignant Melanoma

61. Most common and least malignant
4.4.3 Summarize the characteristics of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.
Basal Cell Carcinoma
Most common and least malignant
Starts in stratum basale – cells can no longer form keratin and invade the dermis and hypodermis
Shiny, dome-shaped
Slow-growing
99% curable
Surgical removal

62. Squamous Cell Carcinoma Starts in the stratum spinosum
4.4.3 Summarize the characteristics of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.
Squamous Cell Carcinoma
Starts in the stratum spinosum
Grows rapidly and can metastasize to the lymph nodes
Treated with surgical removal and radiation
Scaly and red

63. Cancer of the melanocytes
4.4.3 Summarize the characteristics of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.
Malignant Melanoma
Cancer of the melanocytes
Metastasizes quickly to lymph and blood vessels
50% survival rate
Spreading black to brown patch

64. Stages of Melanoma
Least Serious
Most Serious

65. American Cancer Society ABCDE Rule A – Asymmetry – sides don’t match
4.4.3 Summarize the characteristics of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.
American Cancer Society
ABCDE Rule
A – Asymmetry – sides don’t match
B – Border irregular – not smooth
C – Color – different colors (black, brown, tan, blue, red)
D – Diameter – larger than 6 mm
E – Evolution – changes with time

66. Border
Evolution
Asymmetry
Diameter
Color