1. The Respiratory System
Mr. Glatt
14-15

2. The Respiratory System

3. Function of the Respiratory System
To bring about the exchange of oxygen and carbon dioxide between our blood and the air
Oxygen in
Carbon dioxide out
Why is this important?
Cells need oxygen to complete cellular respiration
Glucose + Oxygent  Cabon Dioxide + Water + ATP (Energy)
Carbon dioxide produced in this process becomes toxic to the body if it is not removed

4. Structures Nose and Nasal Cavity
Provides a passageway for air to enter the body during respiration
Air is filtered, moistened and warmed as it passes through these structures

5. Structures Pharynx
Passage from the back of the mouth and nasal cavity that leads to the trachea & larynx
Commonly known as the throat!

6. Structures Trachea
The trachea is the tube that provides a passageway for air from the pharynx (throat) to the lungs
Commonly known as the windpipe
At the top of the trachea is a flap of tissue called the epiglottis
The epiglottis closes off the trachea when we swallow
The larynx or voicebox is also located at the top of the trachea
It contains vocal cords

7. Structures Bronchii
The bronchii are the two large airways that branch out from the trachea and enter the right and left lung.
Each large bronchus branches out into smaller and smaller bronchii

8. Structures Bronchioles & Alveoli
Bronchioles are the smallest passageways in the lungs. Each bronchiole leads into a clump of alveoli
Alveoli are tiny air sacs that are clumped together like bunches of grapes
Alveoli are surrounded by capillaries (thin walled blood vessels)
Alveoli have very thin walls
This is where oxygen and carbon dioxide are exchanged between the lungs and the blood

9. Gas Exchange Inhaled Air Exhaled Air 21 percent OXYGEN gas
.04 percent CARBON DIOXIDE gas
Exhaled Air
15 percent OXYGEN gas
4 percent CARBON DIOXIDE gas

10. How Breathing Works
At the bottom of the chest cavity is a muscle called the diaphragm
When the diaphragm contracts it causes the chest to expand
When the chest expands a vacuum is created
Low pressure air inside lungs
Higher pressure outside lungs
Air then rushes into lungs due to pressure difference
When diaphragm relaxes chest gets smaller and air is forced out due to increased pressure inside chest

11. What Regulates Breathing Rate?
Breathing rate is under autonomic control although we have the ability to consciously control our breathing rate
The medulla oblongata is a specialized portion of the brain that regulates or breathing rate
Measures and monitors carbon dioxide levels in the blood
As carbon dioxide levels increase the medulla oblongata sends impulses to the diaphragm to contract more quickly causing breathing rate to increase