1. Respiratory system

2. I. Function
Exchange oxygen and carbon dioxide with the environment (external respiration)

3. II. Pathway of Airflow Mouth/nose Nasal cavity
Pharynx (throat, back of mouth)
Trachea (windpipe)
Lungs (Bronchi, bronchioles, alveoli)

4. A. Mouth/nose Air enters mouth or nose Nose Cleans—nasal hairs, mucous
Moistens
Cilia and mucous trap dust particles
Best for air to enter here

5. B. Nasal Cavity
Warms air
Moistens air
Cilia continue to filter

6. C. Pharynx Back of mouth; throat Passage for food and air
Epiglottis is located here

7. D. Trachea “Windpipe” Kept open by C-shaped rings of cartilage
Contains cilia and mucous for filtering
Larynx (voice box)-lies above trachea; largest piece of cartilage is the “Adam’s apple”

8. E. Lungs 1. Trachea is divided into bronchi (2 tubes)
2. Bronchi divide into smaller tubes called bronchioles
3. Bronchioles lead to alveoli (air sacs)
4. Gas exchange occurs

9. Gas exchange 3 things that happed to inhaled air:
1. In lungs, oxygen diffuses into the blood, via alveoli
2. Carbon dioxide diffused into the lungs, via alveoli
3. Water vapor is added
4. Air exits the lungs
B. Inhalation & exhalation controlled by diaphragm

10. IV. Control of Respiration
Involuntary
Controlled by medulla oblongata in the brain (brain stem)

11. V. Respiratory Disorders
Asthma: Constricted bronchioles trigger coughing, wheezing, and breathlessness.
Acute bronchitis: Temporary inflammation of bronchi due to infection.
Chronic bronchitis: Long-term inflammation of airways due to smoking or pollutants.

12. Emphysema: Breakdown of alveoli structure, often due to smoking or pollution.
Pneumonia: Alveoli filled with fluid and dead white blood cells due to bacterial infection.

13. VI. Respiratory Fun Facts
The lungs contain 1,490 miles of airways.
Hiccups occur when the diaphragm contracts rapidly, forcing air through vocal cords.
Every minute, about 6.5 liters (13 pints) of air is breathed in.
Adult lungs hold an average of 3 liter (6 pints) of air.

14. Excretory System

15. I. Functions
Excretion: Remove metabolic wastes (excess salts & water, carbon dioxide, & urea)
Liquid wastes are removed (urine); large intestine aids in the removal of solid wastes (feces)

16. II. Composition Skin Lungs Liver Kidneys & Associated organs
(Urinary bladder, ureters & urethra)

17. A. Skin (also part of integumentary system)
1. Sweat is released from the pores of your skin.
2. Sweat is a mix of 3 metabolic wastes: water, salts, & urea.
3. Sweating:
a. Cools the body
b. Excretes metabolic wastes

18. B. Lungs 1. Exhalation of carbon dioxide & water vapor
2. Also a major organ of the respiratory system

19. C. Liver 1. Largest internal organ 2. Functions in 3 systems
a. Excretory: Produces a waste called urea
b. Circulatory: removes & breaks down old red blood cells
c. Digestive: produces bile; detoxifies blood; maintains glucose levels

21. D. Kidney & Associated Organs (Urinary System)
1. Composition
a. 2 kidneys
b. 2 tubes called ureters
c. 1 urinary bladder
d. 1 urethra

22. 2. Kidneys a. Filters the blood through a network of capillaries
b. Needed substances are returned to the blood (99% of water)
c. Produces urine (water, salts, & urea)

23. III. Flow of Urine B. Carried by ureters C. Stored in urinary bladder
A. Produced by kidneys
B. Carried by ureters
C. Stored in urinary bladder
D. Brought to the outside of the body by the Urethra

24. IV. Fun Facts 
Each hour, the kidneys filter up to 12 pints (7 liters) of fluid from the blood.
Urine is 95% water.
On average we produce 2 L of urine a day.
The bladder normally holds mL, but can be force to hold up to 800 mL.