Integumentary System & Body Membranes. Body Membranes A membrane = a very thin strong pliable...

Integumentary System & Body Membranes

Body Membranes

• A membrane = a very thin strong pliable tissue which covers, lines or connects parts of an organism

• Simple organs

• 2 types of body membranes: Epithelial and Connective

Epithelial Membranes

Contain an epithelial sheet with an underlying CT

1. Cutaneous Membrane: Skin

– Superficial epidermis is stratified squamous epithelium

– Dermis is dense fibrous connective tissue

– Dry membrane

Epithelial Membranes

2. Mucous Membranes: (Mucosa)

– Epithelium on loose connective tissue• Stratified squamous or simple

columnar

– Lines body cavities that open to the outside.

– Wet membrane

Epithelial Membranes

3. Serous Membrane (Serosa):

– Simple Squamous epithelium on areolar CT

– Parietal layer lines body cavity

– Visceral layer covers outside of organs

– Serous fluid secreted by both layers allows organs to slide easily

Serous Membranes To Know:

• Peritoneum- membranes of the abdominal cavity and its organs

• Pleura- membranes of the lungs and thoracic cavity

• Pericardium- Membranes around the heart

CT Membranes

• Synovial Membranes: Only connective tissue.

– Fibrous capsules lining joints.

– Secrete synovial fluid.

– Line sacs of CT called bursae & tendon sheaths

Let’s go back to the skin, our cutaneous membrane.

Ravaged

Scared

But Repairable!

How did this pimple happen to YOU?

• .

Questions?

• What is acne?• What causes it?

• How is it treated? • What doesn’t cause it?

• Who gets it?

In order to find out how we all get pimples, we need to know the parts of

the skin.

Review parts of the skin

Figure 5.1

What is skin?

• Its an organ

• Length of replacement? Youth: 28-30 days, Elderly 45-50 days

Is skin the same thing as the integumentary system?

• No.

• Skin is a cutaneous membrane

• Integumentary system includes sweat and oil glands, hair, and nails.

• Integument= covering

What are the jobs of the skin?

• Regulates heat loss.• Excretory functions for urea, salts, and

water. • Water Retention• Manufactures proteins• Synthesizes vitamin D• Integrate with the nervous system for touch

sensation

What are the three layers of the skin?

*

What is the job of the epidermis?• Keratinizes: becomes hard for protection

• Avascular: only the lowest level of the epidermis gain nutrients. That means: the skin you see is all dead! Shedding skin doesn’t hurt!!!

• Contains Melanin: pigment produced by melanocytes.

Layers of the Epidermis

Layers of Epidermis

• Stratum Basale – deepest, only epidermal cells

• Stratum Spinosum-make Keratinocytes

• Stratum Granulosum-fuse cells together

• Stratum Lucidum – only on hands/feet• Stratum Corneum – top layer, filled

with keratin

Epidermis Skin Layers

Granulosum

Spinosum

Lucidum

Basale

Corneum

Skin Color

• Melanin (yellow, reddish brown, or black)

• Carotene• Oxygen bound to hemoglobin in

dermal blood vessels–Poorly oxygenated blood causes

cyanosis

What do Melanocytes do?

• Produces pigment to protect the cells DNA.

Alterations in Skin Color

• Redness (erythema) – embarrassment, fever, allergy

• Pallor (blanching) – fear, anger• Jaundice (yellow) – liver disorder,

excess bile• Bruises – blood escaped circulated

and clots in tissue spaces

What is the job of the dermis?

• Its leather. Protective, strong, living, and houses many other tissues.

• Sweat Glands: maintain body temp. Excrete waste.

• Hair follicles/bulbs: for warmth

• Nerves: pain, pressure, temperature

• Blood vessels: maintain body temp

2 Regions of Dermis

• Papillary layer – contain capillaries for nutrients for epidermis–pain and touch receptors–Regulates temperature

2 Regions of Dermis

• Reticular Layer – deepest skin layer–Blood vessels, sweat and oil

glands, and deep pressure receptors

–Thick collagen strengthens skin

Papillary and Reticular Layers

What is an appendage of the skin?

• Append= to hang on

• These are things that “hang on” or are attached to the skin.

• Appendages include: Glands, Hair, and Nails

• All appendages are part of the epidermis

What is the job of hair and hair follicles?

• Guards the head and eyes as well as respiratory tract from particles & impact.

• Head Hair

• Eyebrows & eyelashes

• Nostrils

• All other body hair is a vestigial feature.

• Hair Follicles grow hair

What are the parts of the hair follicle?

• Root of hair is enclosed in the hair follicle (The hair bulb matrix= zone of growth which contains melanin).

• Hair grows up the shaft to the surface of the skin.

• The bulk of hair is dead. There are 3 layers to hair: 1) Medulla, 2) Cortex, 3) Cuticle (Protection against abrasion, Damage=Split Ends)

Hair Growth

What makes hair look different?

• The amount of melanin secreted

• The shape of the hair is regulated by the shape of the hair follicle which changes the shape of the hair shaft.– Round Hair (straight shaft)= Straight and

Coarse

– Oval Hair= Wavy and Smooth

– Curley Hair (hooked shaft)= Flat

• Used for protection

• The root of the nail is embedded in the skin. Grows from the nail matrix. The cells are heavily Keratinized & die.

• Extends along the nail bed.

• Lunula – moon shaped beginning of nail Fig5.4 pg. 104 Lun= moon

What are the parts of the nail?

Nail Growth

What do the cutaneous glands do?

• Exocrine glands that secrete onto the surface of the skin. Sebaceous & Sweat

– Sebaceous Glands- Produce oil all over the body. Sebum used for softening, water retention, killing bacteria. Increases when testosterone is produced= Oily skin.

– Sweat Glands- helps maintain homeostasis

What are the two types of sweat glands?

• Eccrine Glands: Cover Body, Contain H2O, Salt, Vit. C, Wastes, Lactic Acid

• pH 4-6: antibacterial

• Sweat pores are not easily visible, Contain nerve endings for regulation

• Develop 4th month gestation

And the Other One?

• Apocrine glands- auxiliary and genital areas. Ducts empty into hair follicles.

• Milky-yellowish in color, odorless. Body odor occurs when bacteria eat it. *Thought to be used in excreting pheromones*

• Axilla, groin, areolae, bearded face of males

• Develop 6th month gestation. Pheromones And Mates

Back to those acne questions

Questions?

• What is acne?-Acne is a disorder resulting from the action of hormones and other substances on the skin's oil glands (sebaceous glands) and hair

follicles

Questions?

What causes it? The hair, sebum, and keratinocytes that fill the narrow follicle may produce a plug, which is an early sign of acne. The plug prevents sebum from reaching the surface of the skin through a pore. The mixture of oil and cells allows bacteria Propionibacterium acnes (P. acnes) that normally live on the skin to grow in the plugged follicles. These bacteria produce attract white blood cells that cause inflammation. When the wall of the plugged follicle breaks down, it spills everything into the nearby skin – sebum, shed skin cells, and bacteria – leading to lesions or pimples. Hormonal changes , heredity, and some medications can cause acne.

Questions?

How is it treated? Benzoyl peroxide – destroys P. acnes, and

may also reduce oil productionResorcinol – can help break down blackheads

and whiteheadsSalicylic acid – helps break down blackheads

and whiteheads. Also helps cut down the shedding of cells lining the hair follicles

Sulfur – helps break down blackheads and whiteheads

Questions?

What doesn’t cause it? Chocolate, caffeine, greasy foods, dirt,

stress

Questions?

Who gets it? (Hint its not nobody)

anybody

slows down after 40 or 50.

So here is how it happens…

orAcne

Treatment Video

What is the job of the hypodermis?

• Anchors the skin

• Shock absorber

• Insulates from temperature change

• Gives shape to fatty areas of the body

Body Fat I.Q.

Why do you not have wrinkles when you’re young?• Collagen fibers: Strong and keep the skin

hydrated (attract H2O).• Elastic fibers: Keep skin elastic. Like all

elastic its less so after time. • Loose fat in the hypodermis. = sagging• Decrease in subcutaneous tissue, causes

dryness, cold sensitivity, and bruising in the elderly

What causes goose bumps?

• Smooth muscles called Arrector pili that attach to hair follicles contract.

• Pulls the hair up and tugs on the skin causing dimples thus bumps in the skin

What happens when the epidermis and dermis separate?

• A blister

• Caused by friction or burns.

Review Burns and Skin Cancer

• What are the ABCD’s of Skin Cancer?

• What are the 3deg. Of Burn?

Skin Cancer

LinkBurns

• 1st degree – epidermis; EX- sunburn• 2nd degree – epidermis & upper dermis

(blisters)• 3rd degree – full thickness; no

regeneration• Critical

– Over 25% 2nd degree– Over 10% 3rd degree– 3rd degree face, hands, or feet

TWO LIFE THREATENING PROBLEMS

1. Loss of fluid → dehydration & electrolyte imbalance → shutdown of kidneys → circulatory shock

2. Infection

Rule of Nines

Allows a quick estimation of burned area of body

Diseases of the Skin and Aging

Brace Yourself

Skin Cancer

Squamous Cell Carcinoma

Basal Cell Carcinoma

Skin Cancer Malignant Melanoma

Recognizing MelanomaABCD

• A – asymmetry

• B – border irregularity

• C – color

• D – diameter

Problems of the skin

• Bedsores or Decubitus Ulcers- Caused by pinching off of the blood supply to the skin. Occurs over bony areas of the body.

Alopecia

• Fancy word for balding

• By age 50, 1/3 of your hair follicles may be lost

• Severe alopecia can happen to anyone at any age and is not thought to be genetic. ALL BODY HAIR is lost!!!

Infections and Allergies of Skin

• Athlete’s foot (tinea pedis) – fungus

More Diseases

• Boils and carbuncles – inflammation of hair follicles and sebaceous glands

And another Disease

• Cold sores – herpes simplex virus – activated by emotional upset, fever or UV radiation

Infections and Allergies of Skin

• Contact Dermatitis – itching, redness, and swelling caused by exposure to chemicals (poison ivy)

Still more Disease

• Impetigo – pink, water-filled, raised lesions that develop a yellow crust and rupture – caused by staphylococcus

Infections and Allergies of Skin

• Psoriasis – chronic condition of reddened epidermal lesions covered with dry scales – triggered by trauma, infection, hormones, stress

Vitaligo

• Three possible causes– Autoimmune attack– Malfunctioning nerves– Self destructive cells

• Some treatments such as creams are effective in early stages.

• Can effect anyone.

WARTS

• Uncontrolled growth of epithelial skin cells

• Papilloma virus (HPV)

• Common warts

• Foot (plantar) warts

• Flat warts

• Genital warts

Half Man Half Tree TreeMan

Feeling Blue?

Feeling Blue?

• Paul Karason says his face turned blue after using a silver extract to treat dermatitis

Blue Fugates of Troublesome Creek

Administering Medications

• Transdermal - skin patches for nicotine, motion sickness, birth control – slow absorption

• Subcutaneous – insulin – moderate absorption

• Intramuscular – vaccines – rapid absorption

Developmental Aspects

• 5th month – fetus covered with downy hair (lanugo) that is shed by birth

• Adolescence – skin and hair become more oily as sebaceous glands are activated (acne)

Developmental Aspects

• Aging – hair thinning and baldness – males

• Gray hair – decreasing amount of melanin deposited – caused by anxiety, protein-deficiency, chemotherapy, excessive vitamin A, genetics

What are the problems with smoking and sun on the

epidermis?• Leathery skin

• Cold sore (herpes outbreak)

• Depressed immune system

• All from DNA damage.

Skin Pop Quiz

1. A 33 year old factory worker who processes several different kinds of chemicals presents with itching and redness. The diagnosis is:

a. tinea pedis

b. psoriasis

c. contact dermatitis

d. impetigo

1. A 33 year old factory worker who processes several different kinds of chemicals presents with itching and redness. The diagnosis is:

a. tinea pedis

b. psoriasis

c. contact dermatitis

d. impetigo

2. A 43 year old woman who has played outdoor tennis since the age of 8 has a few small lesions on her face that appear shiny with a central ulcer. The diagnosis is:

a. malignant melanoma

b. basal cell carcinoma

c. squamous cell carcinoma

d. malignant keratinoma

2. A 43 year old woman who has played outdoor tennis since the age of 8 has a few small lesions on her face that appear shiny with a central ulcer. The diagnosis is:

a. malignant melanoma

b. basal cell carcinoma

c. squamous cell carcinoma

d. malignant keratinoma

3. A 16 year old patient who recently suffered a liver laceration (cut) during a car accident noticed that the white of his eyes has begun to turn yellow. The diagnosis is:

a. impetigo

b. erythema

c. seborrhea

d. jaundice

3. A 16 year old patient who recently suffered a liver laceration (cut) during a car accident noticed that the white of his eyes has begun to turn yellow. The diagnosis is:

a. impetigo

b. erythema

c. seborrhea

d. jaundice

4. A 20 year old college student presents with small blisters that sting on the inside of his mouth. The blisters are filled with fluid and he notices that they reappear when he becomes stressed or upset for long periods. The diagnosis is:

a. cold sores

b. carbuncles

c. hematomas

d. decubitus ulcers

4. A 20 year old college student presents with small blisters that sting on the inside of his mouth. The blisters are filled with fluid and he notices that they reappear when he becomes stressed or upset for long periods. The diagnosis is:

a. cold sores

b. carbuncles

c. hematomas

d. decubitus ulcers

5. A mother delivers a 24 week old baby. The baby has blue fingers and lips due to under development of its lungs. The diagnosis is:

a. pallor

b. cyanosis

c. erythema

d. jaundice

5. A mother delivers a 24 week old baby. The baby has blue fingers and lips due to under development of its lungs. The diagnosis is:

a. pallor

b. cyanosis

c. erythema

d. jaundice