Skin

And

Body Linings

1.

List the function of the skin and body membranes:

3

-1 Line or cover body surfaces

-2 Protect body tissues

-3 Lubricate body surfaces

2.

Classify the two types of body membranes.

Classification of Body MembranesClassification of Body Membranes

Slide 4.2Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

(a)Epithelial membranes

Cutaneous membrane

Mucous membrane

Serous membrane

(b)Connective tissue membranes

3.

Identify the Cutaneous membrane and list two traits.

Trait # 1:

A dry membrane

Trait # 2:

Outermost protective barrier

4.

Describe the superficial epidermis of the skin:

The outer skin is stratified squamous epithelium. Hardened by Keratin deposits to make it water proof.

5.

What makes up the underlying dermis of the skin?

“Mostly dense connective tissue”

6.

Mucous Membranes!

Four traits.

-1 Surface epithelium varies according to where it is.

-2 Basement membrane is a Loose Connective Tissue called the LAMINA PROPRIA.

-3. Lines all body cavities that open to the exterior body surfaces.

-4. Often adapted for absorption and secretion.

7.

Surface?

Simple Squamous Epithelium

Underneath?

Areolar connective tissue.

Function?

Lines body cavities that are CLOSED

Function of the serous fluid?

To separate the two serous layers

8.

Differentiate the Serous membrane pairs:

Parietal serous lines the interior body wall.

Visceral serous lines the organs themselves.

9.

Describe three specific serous membranes:

-1 Peritoneum:

Lines the abdominal cavity.

-2. PLEURA

Lines the lungs

-3 PERICARDIUM

LINES THE HEART

10.

Describe the Synovial Membrane:

Connective Tissue MembraneConnective Tissue Membrane

Slide 4.7Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Synovial membrane

Connective tissue only

Lines fibrous capsules surrounding joints

Figure 4.2

11.

List the four parts of the integumentary system.

Skin

Sweat and Oil Glands

Hairs

Nails

12.

List 9 functions of the skin, and tell how this function is accomplished:

-1

Protection from Mechanical Damage(bumps):

-1 Physical barrier contains keratin, which toughens cells, and pressure receptors which alert the nervous system to possible damage.

-2 Protection from Chemical Damage

-2 Has relatively impermeable keratinized cells; contains PAIN receptors which alert the nervous system to possible damage.

-3 Protection from Bacterial Damage

3

-3

a- unbroken surface

b- acidic skin secretions

c- Phagocytes to ingest invading bacteria

-4 Protection from ultraviolet radiation

-4

Melanin produced by melanocytes sheilds deep tissue from U.V. radiation.

-5 Protection from thermal damage

Contains heat/cold/pain receptors

-6 Protection from Desiccation (drying out)

-6 Outer epithelium is full of keratin which prevents unwanted movement of water.

-7 Regulates heat loss

2

a- Heat loss: By activating sweat glands and allowing blood to flush into skin capillary beds.

-b Heat retention:

By not allowing blood to flush into skin capillary beds.

-8 Excretes liquid body waste!

Urea and Uric Acid are contained in perspiration produced by the sweat glands.

-9 Synthesizes vitamin D.

Modified cholesterol molecules in skin are converted to vitamin D by sunlight

13.

Explain the role that Keratin and Sebrum have in maintaining the skin:

KERATIN:

Hardens the skin cells and makes them waterproof.

Sebrum

Oily secretion that makes the skin soft and pliable.

POP’S NOTE!!!

SKIN LAYERS:

EPIDERMISDERMIS

HYPODERMIS

OUTSIDE

INSIDE

14.

Describe the structure of the skin:

EPIDERMIS

(OUTER LAYER)

-1. Stratified squamous epithelium

-2 Hardened by Keratin

Dermis ( middle)

-1 Dense connective tissue

HYPODERMIS (inner)

-1 Not part of the skin

-2 Anchors skin to the underlying organs.

-3 composed mostly of adipose tissue.

15. Discuss the composition of the Epidermis:

1.Composed of 5 layers called Strata.

2.Avascular

3.Contains Keratinocytes

4. New cells created only at layer next to the dermis.

Pop’s Note!

Epidermis is in 5 layers.

Stratum CorneumStratum Lucidum

Stratum GranulosumStratum Spinosum

Stratum Basale

16. Discuss the birth, rise, death, hardening, and flaking away of the epidermal cells.

-1 Birth

“Cells are born by mitosis in the stratum basale.”

Only layer that receivesA good blood supply!

-2 Rise!

New cells get pushed up into the stratum spinosum.

Very little blood supply

-3 Death of skin cells.

Cells now pushed on up into the Stratum Granulosum. Cells die from lack of blood supply.

-4. Hardening

Pushed on up into the stratum Lucidum, the cells fill up with Keratin.

-5 Flaking

Cells pushed on up to the stratum Corneum.

Dead cells called “horny” cells, get rubbed off by friction.

17. Describe the two layers of the dermis:

PAPILLARY LAYER

-1 Projections called the dermal papillae penetrate the dermis.

PAPILLARY LAYER

-2 These dermal papillae contain capillary loops to keep a fresh blood supply.

PAPILLARY LAYER

-3 Dermal papillae also contain pain and touch receptors.

Reticular layer Pop’s Note! Its under the papillary layer

-1 blood vessels

-2 glands

-3 nerve receptors

CONTAINS

Lab day tomorrow!Model of epidermal layers

Begin day # 2

18. Discuss the role of the Collagen fibers and the Elastic Fibers that are found in the dermis:

COLLAGEN FIBERS-1 Collagen fibers make the skin tough.

-2 Binds and holds water to keep the skin hydrated.

Elastic Fibers-1 Elastic fibers make the skin stretchy and flexible.

-2 These fibers decrease with age.

19. List and Identify 5 types of sensory receptors found in the skin:

MEISSNER’S CORPUSCLESTouch

receptors

PACINIAN CORPUSCLES

Deep pressure receptors

BULBS OF KRAUS

Cold Recptors

RAFINNIAN RECEPTORS

Heat receptors

NOCICEPTORS

Pain Receptors

20. Identify Decubitus ulcers, explain what causes them, and give the symptoms that indicate that a decubitus ulcer is developing:

Causes:-1. Bedridden patients are not turned properly or dragged continually across the bed.

-2. Weight of the body puts pressure on the skin!

-3. Blood supply to the skin is cut off, and the skin becomes pale or blanched at the pressure points.

Symptoms?

1.Red skin

2.Cells die

3. skin splits

4.Bed sore appears.

Pop’s Note!

This happens a lot in hospitals and nursing homes. Keep checking for signs of neglect.

21.

Describe three skin color determinants:

M E L A N I NYellow, brown, or black pigments

C A R O T E N EOrange – yellow pigment that you absorbed from some vegetable.. Like carrots!

Hemoglobin-1 Red coloring from blood cells in dermis capillaries.

1 of 2

Hemoglobin-2 Oxygen content determines the extent of the red coloring.

MELANOCYTES

What?

Cells that produce the pigment Melanin.

MELANOCYTES

Where?

Located mainly in the stratum basale of the epidermis.

23.

Describe the

Tanning process:

Skin is exposed to sunlight

Melanocytes in the stratum basale begins to produce melanin.

Stratum basale cells begin to eat the melanin, and turn brown

Basale cells work their way to the surface of skin and the skin is Tanned

24. Describe the role of the Sebaceous glands:

-1 Produce Oil

-2 Lubricates skin

-3 kills bacteria

-4 Most sebaceous glands empty into hair follicles.

When do the Sebaceous glands become active?

“At PUBERTY”

What problems may this cause?

1.Oil puddles up: forms a white head.

2.Oil dries: forms a blackhead

3.Bacteria come in to feed on oil: Pimples

26. Differentiate the two types of sweat glands:

E C C R I N ESweat passes through ducts out to the skin surface through pores, or empties into hair follicles.

APOCRINELarge glands found in the genital and armpit area. Secretions may be white or yellowish in color.

Pop’s Note!

Which sweat gland causes pimples?

Which sweat gland causes odor?

Apocrine glands cause odor.

Eccrine glands cause pimples.

Both the results of bacteria coming to feed on the oil.

27. Describe the composition of sweat?

Eccrine sweat Apocrine Sweat

Water Water

Salt, Urea, and Uric Acid

Salt, Urea, and Uric Acid

Lactic Acid (draws mosquitoes)

Fats and proteins (draws bacteria)

Location: Body Location: armpits and Genitals

What other substance do you know that is made of the same stuff as sweat?

URINE

28. What is the function of sweat?

-1 Remove excess heat

-2 excrete waste products

-3 acidic nature kills parasitic bacteria.

29. What causes sweat to have an odor?

When the bacteria come to feed, they USE THE TOILET. The odor, is aroma of their FECES!

30. What was the original purpose of hair in early man?

Primitive man had a full coat of hair. It served two functions:

-1 Fluffed up, it made them look bigger!

-2 Fluffed up, it would keep them warm.

31. What evidence do we have that man once produced a full coat of hair?

The CHILL BUMPS that pop up on our body when we are afraid or cold are really HAIR FOLLICLES.

32. Identify the following hair related structures:

H A I R F O L L I C L E

. A flexible epithelial structure that the hair grows out of.

H A I R R O O TThe part of the hair that is enclosed in the hair follicle.

H A I R S H A F TThe part of the hair that is projecting out of the scalp or skin.

H A I R B U L B

M A T R I XThe living part of the hair. Down deep in the hair follicle. New hair cells produced by mitosis

33. Explain how living hair cells that are undergoing mitosis in the hair bulb matrix becomes the non-living hair that we find on our body:

As the young daughter cells are pushed farther and farther away from the hair bulb matrix, they become full of keratin and die.

34. Discuss the components of the hair shaft:

Hair AnatomyHair Anatomy

Slide 4.19Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Central medulla

Cortex surrounds medulla

Cuticle on outside of cortex

Most heavily keratinized

Figure 4.7b

Begin day 3

35. What causes the phenomenon called “Split Ends”?

The cuticle begins to wear away at the end of the hair shaft, allowing the keratin fibrils in the inner hair regions to frizz out.

36. What are the ARRECTOR PILI? Discus their function:

A R R E C T O R P I L I

What ?

Small bands of smooth muscle that connect to each side of a hair follicle.

A R R E C T O R P I L I

Function?

When these muscles contract, they make our hair fluff up—or stand on end.

37. What is a NAIL?

A nail is a scalelike modification of the epidermis that corresponds to the hoof or claw of other animals.

38. Describe the following

Nail structures:

FREE EDGE

Tip of the nail above the skin line.

Nail folds.Skin that

Overlaps the

Bottom of the

nail.

cuticle. The thick nail

Fold at the

Bottom of the

nail.

Nail bed.The stratum

Basale of the

Epidermis that

Is under the nail.

Nail matrix.Portion of the

Nail bed where

Nail growth

Occurs.

Lunula.The white

Cresent of the

Nail that protects

The nail matrix.

39. Identify the following infections of the skin:

ATHLETE’S FOOT

An itchy red peeling condition of the skin between the toes, resulting from fungus infection.

Boils and Carbuncles

Infection of the hair follicles and sebaceous glands. Carbuncles are composite boils typically caused by bacteria.

Cold Sores

.Small fluid filled blisters that itch and sting. Caused by the herpes simplex virus.

Contact dermatitisItching, red rash usually caused by coming into contact with stuff like poison ivy.

Impetigo

.Pink, water-filled, raised lesions tht develop a yellow crust and eventually rupture. Caused by contagious bacteria. Common in young children.

PsoriasisA chronic condition characterized by red epidermal lesions covered with dry silvery scales. May be disfiguring. Cause unknown. May be hereditary.

40. What is meant by a skin BURN?

A burn is tissue damage and cell death caused by intense heat, electricity, sunburn, or certain chemicals like acids.

41. Why are burns so dangerous?

-1 The body loses its supply of fluids as these seep from the burned surfaces.

-2 Dehydration and electrolyte imbalance follows.

-3 Kidneys can shut down, and the patient can go into circulatory shock as the blood volume drops.

42. What is the “Rule of Nines”?

3

Rules of NinesRules of Nines

Slide 4.26Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Way to determine the extent of burns

Body is divided into 11 areas for quick estimation

Each area represents about 9%

43.Describe 1st degree burns:

-1 Only the epidermis is damaged.

-2 Skin is red and swollen

44. Describe 2nd degree burns:

-1 Epidermis and upper dermis are damaged.

-2 Skin is red with blisters

45. Describe 3rd degree burns:

-1 Destroys entire skin layer

-2 Burn is gray-white or black.

46.What is Cancer?

Abnormal cell mass that develops when mitosis speeds up and creates abnormal cells.

46. Describe the two types of cancer:

BENIGN

Cancer is encapsulated and will not spread.

Malignant

Metastasized (moves) to other parts of the body.

48. Describe a Basal Cell Carcinoma:

-1 Least malignant

-2 Most common type

-3 Arises from statum basale

49. Describe a Squamous cell carcinoma:

-1 Arises from stratum spinosum

-2 metastasizes to lymph nodes

-3 early removal allows a good chance of cure.

50. Describe a malignant melanoma:

-1 most deadly

-2 cancer of melanocytes

-3 metastasizes to lymph and blood vessels

-4 Detection uses the ABCD rule.

51. Describe the ABCD rule of cancer determination:

A = Asymmetry

The two sides of the pigmented spot or mole do not match.

B= Border irregulatity

The borders of the lesion are not smooth but exhibit indentations.

C=Color

The pigmented spot contains areas of different colors

D = Diameter

The spot is larger than 6mm in diameter.

52.Aging!

-1 Amount of subcutaneous fat decreases. People become intolerant to cold.

-2 Sebrum production drops. Skin gets drier and itchy.

-3 Epithelium gets thinner. People bruise easier.

-4 The amount of ELASTIN in the skin drops. Skin won’t snap back. It starts to sag.

-5 Hair becomes thinner and falls out.

53. What causes hair to turn gray and then white?

Genetically controlled by a “delayed reaction” gene.

54.Are bald headed men really bald? Explain.

No, they are not.

The hair is just very tiny with NO MELANIN at all in it. In fact, the hair may never leave the hair follicle, but its still there.

55. What causes blisters?

Friction, like shoes rubbing, causes the epidermis and dermis to separate! Fluid fills the space. Blister forms..

56. Identify the following skin problems:

HEMATOMABruising occurs as blood leaks out of the capillaries and clots up in the tissues.

JaundiceYellow skin due to a liver problem. Bile pigments accumulate in the skin tissues.

CYANOSISCommon in patients that have heart attacks or breathing problems. Lack of oxygen in the blood causes the skin to turn blue.

The end