1. Endocrine System

2. Structures of the Endocrine System
Composed of glands that secrete hormones.
Hormones = chemical messengers that regulate the activity of other cells.
Glands:
Pituitary gland
Thyroid
Parathyroid
Adrenal glands
Pancreas
Ovaries, testes

3. Functions Influences growth, development, metabolism.
Helps maintain homeostasis.

4. Our defense against disease
The Lymphatic System:
Our defense against disease

5. Lymphatic System
Structures: white blood cells, thymus, spleen, lymph nodes and vessels
Function: Protect against disease.

6. Important Terms Immunity: Resistance to pathogens or their toxins.
Pathogens: Agents that cause disease (Ex: Bacteria, Viruses, Fungi, Protozoans).

7. Sources of Immunity
Skin/ mucus membranes keep foreign particles from entering the body.
White blood cells
Engulf and destroy foreign particles
Produce antibodies (which attack specific pathogens)
Vaccines: weakened form
of a pathogen that causes
immunity.

8. How the Body Fights Infection
Fever: Bacteria and viruses cannot replicate as fast in higher temperatures.
Inflammation: Infected area is walled off to prevent spread of infection.
Some white blood cells phagocytize (eat) pathogens.
T-cells kill infected cells and prevent pathogens from replicating. Also stimulate growth of B-cells.
B-cells produce antibodies

10. Immune System Disorders
Allergies:
Overreaction of the immune system to something in the environment.
Cells produce histamine, chemicals that cause the symptoms of allergies.
Autoimmune disease:
Immune system attacks the body’s own cells.
Ex: Rheumatoid arthritis is caused by destruction of joints by immune system.
AIDS:
Caused by HIV, destroys T-cells

11. Did you know…More than 90% of people claim to wash their hands but only about 60% actually do and only about 16% do it correctly.

12. The Integumentary System

13. Organs
Hair
Skin
Nails
Sweat glands
Oil glands

14. Skin Functions Protection
barrier against infection, injury, UV radiation
Maintain constant body temperature
Sweat
When hot, blood flow increases
When cold, blood flow decreases

15. Hair Functions On head helps keep head cool/warm Protects from the sun
On body
sensation

16. Keep skin and hair soft, inhibits growth of bacteria/fungi
Function of Oil Glands
Keep skin and hair soft, inhibits growth of bacteria/fungi

17. Layers of the Skin Epidermis: top layer, made of dead cells.
Has cells that make melanin (gives skin color)
Dermis: thickest layer of skin. Contains glands, hair follicles, nerves, and blood vessels