Your Respiratory System

1. Your Respiratory System Breathe in – Breathe out!

2. The Respiratory System • Your respiratory system is made up of the organs in your body that help you breathe. • Remember, Respiration = Breathing. • The goal of breathing is to deliver oxygen to the body and to take away carbon dioxide. • The exchange and transport of these two gases (Oxygen & Carbon Dioxide) is the main function of the Respiratory System.

3. The Main Organs of the Respiratory System Lungs • The lungs are the main organs of the respiratory system. • In the lungs oxygen is taken into the body and carbon dioxide is breathed out. • Red blood cells are responsible for carrying oxygen to your cells and they are also responsible for carrying carbon dioxide away from your cells.

4. The Main Organs of the Respiratory System Trachea • The trachea (TRAY-kee-uh} is sometimes called the windpipe. • The trachea filters the air we breathe and branches into the bronchi.

5. The Main Organs of the Respiratory System Bronchus (Bronchi) The bronchi (BRAHN-ky) are two air tubes that branch off of the trachea and carry air directly into the lungs.

6. The Main Organs of the Respiratory System Diaphragm • Breathing starts with a dome-shaped muscle at the bottom of the lungs called the diaphragm (DY-uh-fram). When you breathe in, the diaphragm contracts. • When it contracts it flattens out and pulls downward. This movement enlarges the space that the lungs are in. This larger space pulls air into the lungs. • When you breathe out, the diaphragm expands and relaxes,reducing the amount of space for the lungs and forcing air out. • The diaphragm is the main muscle used in breathing. Diaphragm

7. Why Do We Yawn? • When you are sleepy or drowsy the lungs do not take enough oxygen from the air. • This causes a shortage of oxygen in our bodies. • The brain senses this shortage of oxygen and sends a message that causes you to take a deep long breath---a YAWN.

8. Why Do You Sneeze? • Sneezing is like a cough in the upper breathing passages. • It is the body's way of removing an irritant from the sensitive mucous membranes of the nose. • Many things can irritate the mucous membranes. • Dust, pollen, pepper or even a cold blast of air are just some of the many things that may cause you to sneeze.

9. Why Do You Hiccup? • Hiccups are the sudden movements of the diaphragm. • It is involuntary --- you have no control over hiccups, as you well know. • There are many causes of hiccups. The diaphragm may get irritated, you may have eaten to fast, or maybe some substance in the blood could even have brought on the hiccups.

10. What are Alveoli? • Alveoli are tiny sponge-like air-filled sacs in your lungs that are surrounded by capillaries (microscopic blood vessels). • Your alveoli transfer the oxygen that you inhale into the blood in your arteries, thanks to those tiny capillaries. • The average adult's lungs contain about 600 million of these spongy, air-filled sacs.

11. Oxygen-Poor and Oxygen-Rich Blood • Blood goes into the lungs looking for oxygen. • When it comes into the lungs, it is said to be “oxygen-poor” – it doesn’t have much oxygen. • Blood leaving the lungs has been filled with oxygen. • When it leaves the lungs, it is said to be “oxygen-rich.”

12. The Path of Oxygen • Oxygen enters the respiratory system through the mouth and the nose. • The oxygen then passes through the larynx (where speech sounds are produced) and the trachea which is a tube that enters the chest cavity. • In the chest cavity, the trachea splits into two smaller tubes called the bronchi (bronchus). • Each bronchus then divides again forming the bronchial tubes. • The bronchial tubes lead directly into the lungs where they divide into many smaller tubes which connect to tiny sacs called alveoli. • The inhaled oxygen passes into the alveoli and then spreads through the capillaries into the blood which is in your arteries.

13. The Path of Carbon Dioxide • We breathe out carbon dioxide, so it takes a reverse path than that of oxygen. • Can you figure out the path???