1. The Integumentary System
Ms. Cohen
Anatomy & Physiology

2. What makes up the Integumentary System?-
Skin
Nails
Hair
Glands (variety)

3. What does this system do for you?
Serving as a barrier against infection and injury
Helping to regulate body temperature
Removing waste products from body
Protection against U.V. radiation
Producing vitamin D

4. The layers The skin is composed of two main layers Epidermis Dermis
The hypodermis layer composed of fat and connective tissue

5. Epidermis
Many layers of flattened, scaly, mostly dead epithelial cells. Sheds every days
Protein KERATIN replaces cell components in
these cells.
Keratin is basic structure of hair, nails and calluses. In animals it forms horns, feathers, scales and quills.
New cells produced in this layer and pushed upward

6. Melanocytes located in the _________________________________________
these cells contain the pigment ____________________________
Dark/light skin = same number melanocytes, varying amount melanin
Amount of melanin depends on _________________ and ________
Basement cells of epidermis
Melanin
Heredity and sun exposure

7. Dermis Two Zones Innermost thick layer Living or Dead?
What’s found here?
Two zones of the dermis:papillary zone - loose areolar connective tissue containing collagen and fine elastic fibers;
connects the epidermis to the thicker and denser reticular zone of the dermis
reticular zone - contains dense, irregular and coarse collagen fibers and thick elastic fibers interspersed with fibroblasts,
blood vessels and nerves
Connective tissueContains blood vessels, nerve endings, glands, sense organs, smooth muscles and hair follicles

8. Dermis Layer and Thermoregulation
Blood vessels narrow to ________________
Blood vessels widen to increase blood flow and ________________
Goosebumps trap heat close to skin.
Narrow to conserve heat during cold
Widen to increase blood flow and release heat on warm days.
Trap heat close to the skin.
Question: You appear flush when vessels are narrow or wider?

9. Sebaceous gland Hair follicle Produce oily secretion called sebum
Keeps keratin __________________
Controlled by hormones
What type of gland?
Mildly toxic to bacteria
Can cause _________
Flexible and waterproof
Exocrine - secretes sebum into duct (pathway) onto surface
acne

10. Sweat gland What comes out of here? Function? How does it start? Sweat
Temperature regulation
Nervous system

11. Hair What types of cuts are these?
Hair is produced in dermis by hair follicle
Hair is large column of dead cells that have filled with keratin
Rapid cell division at hair root causes hair growth
Hair gets its color from melanin
How long does hair grow for before it falls out?

12. Nails What do you think cells fill with? ____________
Rapidly dividing cells
What do you think cells fill with? ____________
Nail appear pink. Why? ___________
Growth rate = mm per day