1. Respiratory System Chapter 37

2. Breathing We breathe about 6 liters of air per minute
This is about the same as the heart pumps
Men breathe about 12/minute
Women breathe about 18/minute
Infants breathe about 40/minute

3. Trachea epiglottis vocal cords
Bronchi
two large branches
Bronchioles
hundreds of smaller branches
Alveoli
air sacs
site of gas exchange
very thin

7. The lungs have a greater exposure to the environment than any other part of the body – including the skin.
The air we breath contains dust, smoke, bacteria, noxious gases, etc …
All come in contact with the blood.

8. The lungs have a large surface area
The convoluted surfaces have a surface area of 80m2
This is about ½ the size of a tennis court!

10. Each alveolus is surrounded by blood so that 02 and C02 can exchange

13. The airways must be able to remove particles.
The body does this in two ways
1. Coughing removes large particles

14. 2. Small particles are carried upward by millions of small hairs called cilia.
They vibrate about 1000/minute
Mucus moves 1 – 2 cm/minute
It takes 30 minutes to be cleared.

15. Smooth Muscle Helps you breath
Diaphragm
Smooth Muscle
Helps you breath
This is an inferior view of the diaphragm. This muscle separates the abdominal cavity from the thoracic cavity. *When it contracts it will cause inspiration.