1. Chapter 6
Integumentary System

2. QOD #1/Pre-Quiz
1. T/F The integumentary system only refers to your skin. 2. T/F Your skin contains a waterproofing protein. 3. T/F Your skin has nothing to do with homeostasis. 4. T/F The integumentary system has 4 layers. 5. T/F There is a disorder in which a person grows hair excessively all over their body (werewolves).

3. Pre-Quiz cont..
6. An infected hair follicle is called a A. boil B. mole. C. acne. D. callous. 7. Thickened area caused by excessive rubbing or pressure. 8. A fleshy skin tumor. 9. Overactive and inflammation of the sebaceous (oil) glands.

4. Integumentary System
Membranes of epithelium and connective tissues that cover body surfaces and lines cavities and organs.
2 or more tissues grouped together = organs
4 Membranes
Serous
Mucous
Synovial
Cutaneous (skin)

5. 4 membranes
SEROUS
Lines body cavities that lack openings to the outside
Paritel pleura, parietal peritoneum, visceral pleura, visceral peritoneum
Contains simple squamous epithelial and loose connective tissue
Serous cells secrete serous fluid to lubricate

7. 4 membranes MUCOUS Lines cavities that open to outside of body
Oral & nasal cavities, digestive, respiratory, urinary, reproductive
Contains epithelium and loose connective tissue
Mucous cells secrete mucus

8. 4 membranes
SYNOVIAL
Inner linings of joint cavities, between ends of bones, and freely movable joints
Knees, shoulder, phalanges
Contains loose connective tissue & adipose
Synovial cells secrete a thick, colorless
synovial fluid that lubricate the ends of bones.

9. 4 membranes CUTANEOUS (SKIN) Largest and very versatile organ
Vital in maintaining homeostasis
Regulates body temperature
Limits water loss
Houses sensory receptors
Synthesizes various biochemicals
Excretes wastes
2 .5layers
Epidermis
Dermis
Subcutaneous
Basement membrane separates these layers

10. SKIN EPIDERMIS Outer layer of stratified squamous
Keratinization: older cells harden, cytoplasm fills with strands of tough, fibrous, keratin-waterproof protein (stratum corneum)
Stratum corneum
-avascular, old, hard, dead cells
Stratum basale
-blood supply from dermis-cells grow and divide and move (pushed) up

11. Epidermis cont.. The growth and loss of cells is balanced
Cell reproduction increases where skin is rubbed or pressed regularly, causing thickened areas called calluses.
Functions (protective)
Shields underlying tissues from water loss
Mechanical injury
Harmful chemicals
Keeps out disease

12. Epidermis cont… Contains melanocytes that produce melanin
Absorbs light energy to protect deeper cells from U-V damage-dark pigment.
Produces skin color
Amount of melanin produced and size of granules determines how light/dark your skin is, as well as:
-genetics
-sunlight (U-V)
-blood in surface vessels
(high O2 = pink
low O2 = blue –cyanosis)

14. DERMIS
Inner layer that contains fibrous connective tissue, epithelial smooth, nervous, and blood tissues
Thicker
Tough & elastic (due to collagen & elastic fibers)
Contains blood vessels
Give nutrients to all skin cells and regulates body temp (if hot b.v expand to release heat, if cold b.v contsrict to keep heat in)
Bed sores
Contains nerve fibers, hair follicles, sebaceous glands, and sweat glands

15. SUBCUTANEOUS (hypodermis)
Beneath dermis/continuous from
Contains loose connective tissue and adipose
Insulates
Binds skin to underlying organs

16. ACCESSORY ORGANS Hair follicles
Hair is dead epidermal cells (keratinized)
) Arrector pili muscle
attached to hair follicle
Contracts in cold or upset (goosebumps)
Color from melanin
More=darker
None=albinism
Trichosiderin=red
shaft
Hair follicle
Cell division occurs here

17. Congential generalized hypertrichosis-”werewolves”

18. Sebaceous Glands Attached to hair follicles Holocrine gland
Secrete oily mixture of fat and sebum (cell debris)
Keeps hair and skin soft, pliable and waterproof
* Acne: overactive and inflamed sebaceous gland

19. Nails Keratinized stratified squamous epithelial with hard keratin
Lunula is the growing region.

20. Sweat Glands (sudoriferous)
Sweat=water, salt, waste (urea & uric acid)
Apocrine gland (emotional)
Armpit and groin
Exocrine gland (hair follicles)
Palms and soles of feet
Eccrine gland (heat and exercise)
Forehead, neck, back