1. “beauty is only skin deep…”
INTEGUMENTARY SYSTEM
“beauty is only skin deep…”

2. Body Membranes
Epithelial Membranes: covering and lining membranes include:
Cutaneous membrane (skin)
Mucus membrane
Serous membrane
They all have an underlying layer of connective tissue

3. Cutaneous and Mucus Membranes

4. Cutaneous Membrane Skin
Superficial layer is keratinized stratified squamous
Underlying layer is dense fibrous connective tissue.
Exposed to air making it a dry membrane

5. Mucous membrane
Composed of epithelium resting on a loose connective tissue membrane called a lamina propria.
Lines body cavities that open to the exterior: respiratory, digestive, urinary, and reproductive tracts.
Wet or moist membranes that are continuously bathed in secretions or urine

6. Serous Membranes

7. Serous Membrane
Epithelium resting on a thin layer of areolar connective tissue.
Line membranes that are closed to the exterior (except for the dorsal body cavity and joint cavities)
Occur in pairs:
Parietal layer: outermost layer, fold in on itself to create the:
Visceral layer: layer closest to the organ

8. Parietal vs Visceral

9. Connective Tissue Membrane
Synovial Membrane: composed of soft areolar connective and has no epithelial.
Line the fibrous capsules surrounding joints
Provide a smooth surface and secrete a lubricating fluid
Cushion organs moving against each other during muscle activity.

10. Synovial Membrane

11. SKIN surface area: 1.2-2.2 square meters
considered the largest organ of the body
7% of total body weight (9-11 pounds)
varies in thickness from mm
epidermis replaced every days
thick skin-covers palms, fingertips, soles of feet (5 epidermal layers)
thin skin-covers the rest of the body (4 epidermal layers)

12. SKIN epidermis dermis hypodermis (subcutaneous tissue)
outermost protective shield
epithelial cells
nonvascular
dermis
leathery (hide)
fibrous connective tissue
vascular
hypodermis (subcutaneous tissue)
deepest layer
adipose tissue (fat cells)

14. CELLS OF THE EPIDERMIS keratinocytes melanocytes
most numerous epidermal cell
produce keratin—fibrous protein
waterproof, tough protective covering
tightly connected by desmosomes
melanocytes
found in stratum basale
produce pigment melanin—uv protection for keratinocytes

15. cells (cont) Langerhan’s cells Merkel cells macrophages
play role in immunity
Merkel cells
sensory receptor for touch

16. LAYERS OF THE EPIDERMIS
stratum corneum (horny layer)
outermost layer; dead, keratinized cells
stratum lucidum (clear layer)
found in thick skin only
thin translucent band
stratum granulosum (granular layer)
change in keratinocytes—flattened cells w/ granules
stratum spinosum (spiny layer)
‘prickles’ irregular shape of keratinocytes
bundles of pre-keratin filaments
stratum basale (basal layer)
mostly single row of cells; site of mitotic cell division
10-25% are melanocytes

21. Dermis
Second major skin region containing strong, flexible connective tissue
Cell types include fibroblasts, macrophages, and occasionally mast cells and white blood cells
Composed of two layers – papillary and reticular

22. DERMIS papillary layer reticular layer areolar connective tissue
peglike projection: dermal papillae
free nerve endings, Meissner’s corpuscles, Pacinian corpuscles
dermal ridgesepidermal ridgesfingerprints
reticular layer
80% of the thickness of dermis
dense irregular connective tissue
important cleavage or tension lines--surgery

23. Functions of the Integumentary System
Protection – chemical, physical, and mechanical barrier
Body temperature regulation is accomplished by:
Dilation (cooling) and constriction (warming) of dermal vessels
Increasing sweat gland secretions to cool the body
Cutaneous sensation – exoreceptors sense touch and pain

24. Functions of the Integumentary System
Metabolic functions – synthesis of vitamin D in dermal blood vessels
Blood reservoir – skin blood vessels store up to 5% of the body’s blood volume
Excretion – limited amounts of nitrogenous wastes are eliminated from the body in sweat

25. Skin Color Three pigments contribute to skin color
Melanin – yellow to reddish-brown to black pigment, responsible for dark skin colors
Freckles and pigmented moles – result from local accumulations of melanin
Carotene – yellow to orange pigment, most obvious in the palms and soles of the feet
Hemoglobin – reddish pigment responsible for the pinkish hue of the skin

26. Skin Cancer The three major types of skin cancer are:
Basal cell carcinoma
Squamous cell carcinoma
Melanoma

27. Basal Cell Carcinoma Least malignant and most common skin cancer
Stratum basale cells proliferate and invade the dermis and hypodermis
Slow growing and do not often metastasize
Can be cured by surgical excision in 99% of the cases

28. Squamous Cell Carcinoma
Arises from keratinocytes of stratum spinosum
Arise most often on scalp, ears, and lower lip
Grows rapidly and metastasizes if not removed
Prognosis is good if treated by radiation therapy or removed surgically

30. Melanoma
Cancer of melanocytes is the most dangerous type of skin cancer because it is:
Highly metastatic
Resistant to chemotherapy

31. Melanoma Melanomas have the following characteristics (ABCD rule)
A: Asymmetry; the two sides of the pigmented area do not match
B: Border is irregular and exhibits indentations
C: Color (pigmented area) is black, brown, tan, and sometimes red or blue
D: Diameter is larger than 6 mm (size of a pencil eraser)

34. Skin and Aging
Epidermal replacement of cells slows and skin becomes thinner
Skin becomes dry and itchy
Subcutaneous fat layer diminishes, leading to intolerance of cold
Decreased elasticity and loss of subcutaneous tissue leads to wrinkles
Decreased numbers of melanocytes and Langerhans’ cells increase the risk of skin cancer

35. A B C D E

36. Burns First-degree – only the epidermis is damaged
Symptoms include localized redness, swelling, and pain
Second-degree – epidermis and upper regions of dermis are damaged
Symptoms mimic first degree burns, but blisters also appear
Third-degree – entire thickness of the skin is damaged
Burned area appears gray-white, cherry red, or black; there is no initial edema or pain (since nerve endings are destroyed)

38. Start: midterm exam on Thurs—copy topics body systems
Anatomy-Physiology
Start: midterm exam on Thurs—copy topics
body systems
homeostasis—negative & positive feedback mechanisms
directional terms & body planes
cells—plasma membrane, cell transport, membrane junctions
osmosis—hypo, hyper, isotonic solutions
tissue types
integumentary system
functions
epidermal layers
dermis
skin appendages—hair, nails, sweat glands
skin cancer
Objectives:
notes: integumentary system
work on Chap. 5 study guide—due Thurs