1. Skin and Body Membranes
Chapter 4
Skin and Body Membranes

2. BODY MEMBRANES
_________________________cover surfaces,line body cavities and forms protective-sometimes lubricating –sheets around organs

3. I.Classification of Body Membranes
A) EPITHELIAL MEMBRANES
Covering and lining membranes
All have an underlying sheet of connective tissue

4. 1) Cutaneous Membranes= skin
Superficial epidermis is____________________________________
Underlying dermis is dense(fibrous) connective tissue.The superficial tissue is exposed to air and is a ________________________________
Composed of keratinizing stratified squamous epithelial
Dry membrane

5. 2) Mucous Membranes-made of varying types of epithelial tissue resting on a loose connective tissue called ____________________ and lines all membranes that open to the exterior(hallow organs of respiratory tract,digestive,urinary and reproductive…
Mucosa refers to location,not cellular makeup….But most mucosa are stratified squamous (mouth and esophagus) epithelium or simple columnar (rest of digestive tract)----all wet and bathed in secretions)
Lamina propria

6. 3)Serous membranes(serosa)-
Has a layer of simple squamous epithelium on a thin layer of ________________________________
Serosa are closed to the exterior (except for dorsal body cavities and joint cavities)
Areolar connective tissue

7. Occur in pairs…The __________________lines a specific portion of the ventral body cavity
Parietal layer folds in itself to form ________________-covers outside of the organs in that cavity
Serous layers separated by___________________-secreted by both membranes
Serous fluid
Parietal layer
Visceral layer

8. Serous fluid allows organs to slide against ea
Serous fluid allows organs to slide against ea. Other and cavity w/o friction

9. SEROUS NAMES RELATED TO LOCATION
peritoneum
______________________covers abdominal cavity
____________________-surrounds lungs
_______________________surrounds heart
pleural
pericardium

12. Connective Tissue membranes
Composed of ______________________and has NO epithelial cells-line capsules surrounding joints
Line small sacs of connective tissue called bursae and the tubelike tendon sheath----all cushioning organs against each other and tendon across bone
Soft areolar connective tissue

14. II.The Integumentary Sysyem(skin)-cutaneous membrane
functions –most importantly protective….against mechanical damage,chemical damage,
bacterial damage,
UV effects,thermal effects and dessication(drying out)
---also aids in controlling body heat
---aids in excretion of urea and uric acid
----synthesizes Vitamin D

15. Capillaries and sweat glands work on thermal control
The uppermost layer is full of _____________-and is cornified or hardened-help prevent water loss
Capillaries and sweat glands work on thermal control
____________sense touch,pressure,temperature and pain
keratin
Cutaneous sensory receptors

17. Structure of skin
Epidermis-stratified squamous epithelial capable of keratinizing(hardening)
_________-underneath-mostly dense connective tissue
Epidermis and dermis strongly connected,but some abuse can cause them to separate—interstitial fluid comes between layers making a _____________
_____________is below dermis and mostly adipose----not actually considered part of skin,but attaches skin to organs beneath---works as “shock absorber” and insulates from extreme temperatures
Subcutaneous tissue
dermis
blister

18. 1)Epidermis-
strata
has 5 layers or _______________.From inside out they are stratum basale,spinosum,granulosum,lucidum and corneum
avascular
most cells are ______________________________which make keratin
keratinocytes

19. Stratum basale-closest to dermis and connected along a wavy borderline
Stratum basale-closest to dermis and connected along a wavy borderline.Contains epidermal cells that that get the most nourishment by diffusion from dermis;constant cell division-MILLIONS OF NEW CELLS DAILY(also called stratum germanitivum),daughter cells pushed upward
Stratum Spinosum and stratum granulosum become flatter and increasingly full of keratin

20. When the previous cells die,they form the clear _________________________________-not in all skin regions-only where skin is hairless and extra thick-ie.palms and soles;it secretes a water repellent glycolipid into extracellular space;distant from blood supply,so little nutrients-doomed cells
Stratum lucidum

21. OUTERMOST Stratum corneum—20-30 cells layers thick and is ¾ of epidermal thickness;cornified,shinglelike dad cells,filled w/ keratin;protects lower cells;dandruff sloughs off from here
We have a totally new epidermis every days
___________________pigment that ranges in color from yellow to brown to black produced by melanocytes(in stratum basale).When skin is exposed to sun,this stimulates these cells tomake more of the pigment---THUS tanning
melanin

22. Melanin accumulates in membrane bound granules called __________________.They move to the end of the melanocytes and taken up by keratinocytes .THERE,melanin froms a pigment umbrella over superficial side of nuclei-shielding DNA from UV
_______________and moles are where melanin are concentrated in one spot
melanosomes
freckles

24. 2)dermis-‘hide Papillary layer strong,stretchy
Dermal papillae
Papillary layer
strong,stretchy
dense fibrous connective tissue
___________________upper dermal region;______________-peglike projections from superior surface-many containing capillary loops-thus nutrients;some have pain receptors-___________________ or touch receptors-_________________________________
Free-nerve endings
Meissner’s corpuscles

25. Has whorled rings on soles and palms,increasing friction and gripping ability----genetically determined…..sweat pores provide for fingerprints

26. Reticular layer Pacinian corpuscles
2)_______________________________deepest skin layer w/blood vessels,sweat and oil glands and _______________________________deep pressure receptors;phagocytes act here at reticular layer
Collagen and elastic fibers found in dermis.collagen gives toughness and attract water for hydration.Elasisic fibers give elasticity that declines w/age
Many blood vessels help w/ body temp.homeostasis.skin is red when hot due to engorging of blood
Pacinian corpuscles

27. ___________________________________ happen in bedridden patients not turned regularily-pressure restricts blood supply and redness when pressure is released
Rich nerve supply
Debicutus ulcers

29. C-Skin Color-3 pigments:
1-melanin in epidermis
2-carotene in stratum corneum and subcutaneous tissue
3-O2-rich hemoglobin in dermis
----varying amounts of thr above create the numerous skin colors.Which is showing up more in Caucasians?_________________________
________________________hemoglobin is poorly oxygenated---can happen during heart failure and severe bleeding
hemoglobin
cyanosis

30. What else affects skin color?:
Emotions and various disease states:
___________________-redness-blushing,hypertension,inflammation,allergy
___________________-blanching-pale—fear,anger also anemia,low blood pressure,impaired blood flow
___________________-yellowness-liver disorder
____________-sites wher blood has escaped and clotted in tissue spaces;can happen w/disese or vitamin C deficiency
_________________-clotted blood mass
jaundice
pallor
erythema
hematomas
bruises

31. D.Appendages of the Skin
Cutaneous glands
1-__________________________________-exocrine glands-release secretions to skin’s surface via ducts
a)Sebaceous glands-oil glands-excepts on palms and soles—some open into hair follicle and some to surface
________________-is product-clump of oil and cells;keeps skin moist and prevents hair from drying out
sebum

32. ______________(sudoriferous glands)-many in the skin-2 types: )eccrine glands-all over body and make sweat(mostly water,NaCl,vitamin C and tarces of metabolic wastes(ammonia, urea,uric acid and lactic acid.It is acidic and inhibits bacteria….sweat comes through a poer(not same as facial pores);helps regulate temp.(37 C
Sweat glands

33. Apocrine glands
2)_____________________________-mostly at axillary and genital areas;ducts empty into hair follicles;contains fatty acids and proteins—giving milky/yellowish color.It is odorless,but that changes whe bacteria use it as food:function at onset of puberty regulated by androgens(male sex hormones)----have been connected to sexual foreplay

36. 3-Hair and Hair Follicles.
1)Hairs made by hair follicles and is flexible epithelial structure;root in ________________and shaft protrudes It is formed by mitosis of stratum basale epithelial cells in matrix(growth zone)-become keratinized and die as pushed forward---mostly hair contains protein
Hair has central core called a medulla surrounded by a cortex.This is covered by a cuticle(most keratinized region)-gives strength
Hair pigments made by melanocytes in hair bulb
Hair follice

37. Variety of shapes and sizes(eyebrows v. head then skin hair)
Variety of shapes and sizes(eyebrows v. head then skin hair).If shaft is flat and ribbonlike-hair curly or kinky.If shaft is round-straight or coarse hair
Hair all over except soles,palms,nipples and lips
Fastest growing tissue in body
Have hormonal control

38. 2) hair follicles-contain inner epidermal sheath that forms hair/outer dermal sheath is connective tissue/papilla yield blood supply to matrix in hair bulb
______________________________smooth muscle that raise hair in response to temp
Errector pilli

39. 3) Nails-scalelike product of dermis(corresponds to hoof or nail)
Free edge
Nail matrix
3) Nails-scalelike product of dermis(corresponds to hoof or nail)
Each nail has a _______________,a body(visible and a root(imbedded in skin)
Nail bed in stratum basale and inner ____________________,responsible for growth-cells become keratinized and die
Part appears pink due to vascularization in dermis
___________________ appears white
lunula

41. E.Homeostatic imbalances of skin
1) Infections and Allergies
___________________________-fungal,itchy red ,peeling skin(tinea pedis)
Boils and Carbuncles-inflammation of hair follicles and sebaceous glands—often dorsal neck.Carbuncles are caused by bacteria-esp. Staphylococcus aureus
Athlete’s foot

42. _____________________-small fluid filled(fever blisters)-itch and sting –caused by a herpes simplex virus-can be activated from dormancy from emotions,fever,UV light-usually around lips or oral mucosa
_____________________________-itchy,red,swelling and turns into blisters-exposure to chemicals like poison ivy
Cold sores
Contact dermatitis

43. ___________________-pink,water-filled raised lesions around nose and mouth;w/yellow crust;caused by Staphylococcus
_____________________-chronic overproduction of cells w/ red epidermal lesions—probably autoimmune
impetigo
psoriasis

44. 2-burns-tissue damage and cell death caused intense heat,electricity,UV light or certain chemicals---This can have a domino effect on several organ systems
destroys cells
Life threatening from 1) loss of fluids as they seep from burned surface-dehydrating and fluid imbalance-could shut down kidneys and cause circulatory shock

45. ___________________________-divides body into 11 areas,ea
___________________________-divides body into 11 areas,ea. 9% of total body surface area+ area around genitals-determines % burned
2) infection later is a leading cause of death-after 24 hrs.,pathogens invade the area and multiply quickly
RULE OF NINES

46. 1st degree-only epidermis is damaged-red and swollen
Classification:
1st degree-only epidermis is damaged-red and swollen
2nd degree injury to epidermis and upper dermis-regrowth will occur
1st and 2nd degree are ___________________________burns
3rd degree-destroys entire thickness of skin(full-thickness burns)
Partial-thickness burns

47. Critical if a) over 25% covered w/ 2nd degree b) over 10% 3rd degree OR c) 3rd on face ,hands or feet

50. 3-Skin Cancer Most neoplasms benign(ex-wart) Affect 1/5 americans
_________________________________-least malignant and most common-affects stratum basal so cannot form keratin;boundary between epidermis and dermis lost;fairly slow growing
_______________________________-from stratum spinosum-scalp,ears,hands-grows rapidly,but if caught early,prognosis is good
Squamous cell carcinoma
Basal cell carcinoma

51. ____________________-cancer of melanocytes(5%of skin cancers)-happen where ever there is pigment and often deadly-50% survival w/early detection
ABCD RULE_
a)asymmetry
b)border irregularity
c)color-areas of different color
d)diameter-larger than 6 mm
Malignant melanoma

54. Take notes p. 127 on developmental aspects:
Lanugo-downy hair covering on infant –shed by birth
Newborn has vernix caeosa-white and cheesy and made by sebaceous glands-protection while in womb
Newborn skin thin-milia-accumulations in sebaceous glands(nose and forehead)
Skin and hair more oily during adolescence-acne occurs
Dermatitis-inplammation

55. During old age- subcutaneous tissue decreases-less tolerance to cold/also drier due to less oil/decreasing elasticity/thinning of skin and more bruising
Good nutrition,fluids and cleanliness csn slow loss of elasticity-aggravated by sun and smoking
Hair loses luster and less hair follicles

56. ALOPECIA-hair thinning and baldness
Male pattern baldness-has light vellus hairs
Graying hair
Genetic factor-as gene is expressed,melanin in hair decreases
Also genetic factor in baldness