The Respiratory System

1. The Respiratory System By: Matthew Green

2. The nostrils • At the top of the respiratory system, the nostrils (also called nares) act as the air intake, bringing air into the nose, where it's warmed and humidified. • Tiny hairs called cilia protect the nasal passageways and other parts of the respiratory tract, filtering out dust and other particles that enter the nose through the breathed air.

3. The pharynx (throat) • The pharynx is part of the digestive system as well as the respiratory system because it carries both food and air. • At the bottom of the pharynx, this pathway divides in two, one for food (the esophagus, which leads to the stomach) and the other for air. • The epiglottis, a small flap of tissue, covers the air-only passage when we swallow, keeping food and liquid from going into the lungs.

4. The larynx • The larynx, or voice box, is the uppermost part of the air-only pipe. This short tube contains a pair of vocal cords, which vibrate to make sounds

5. The trachea • The trachea, or windpipe, extends downward from the base of the larynx. • It lies partly in the neck and partly in the chest cavity. The walls of the trachea are strengthened by stiff rings of cartilage to keep it open. • The trachea is also lined with cilia, which sweep fluids and foreign particles out of the airway so that they stay out of the lungs.

6. Bronchi • At its bottom end, the trachea divides into left and right air tubes called bronchi, which connect to the lungs. • Within the lungs, the bronchi branch into smaller bronchi and even smaller tubes called bronchioles. • Bronchioles end in tiny air sacs called alveoli, where the exchange of oxygen and carbon dioxide actually takes place. • Each lung houses about 300-400 million alveoli • The lungs also contain elastic tissues that allow them to inflate and deflate without losing shape and are encased by a thin lining called the pleura. • This network of alveoli, bronchioles, and bronchi is known as the bronchial tree.

7. Alveoli • Every few seconds, with each inhalation, air fills a large portion of the millions of alveoli. • In a process called diffusion, oxygen moves from the alveoli to the blood through the capillaries (tiny blood vessels) lining the alveolar walls. • Once in the bloodstream, oxygen gets picked up by the hemoglobin in red blood cells. • This oxygen-rich blood then flows back to the heart, which pumps it through the arteries to oxygen-hungry tissues throughout the body

8. The Thorax • The chest cavity, or thorax, is the airtight box that houses the bronchial tree, lungs, heart, and other structures. • The top and sides of the thorax are formed by the ribs and attached muscles. • The bottom is formed by a large muscle called the diaphragm. • The chest walls form a protective cage around the lungs and other contents of the chest cavity.

9. The Heart • In the tiny capillaries of the body tissues, oxygen is freed from the hemoglobin and moves into the cells. • Carbon dioxide, which is produced during the process of diffusion, moves out of these cells into the capillaries, where most of it is dissolved in the plasma of the blood. • Blood rich in carbon dioxide then returns to the heart via the veins. • From the heart, this blood is pumped to the lungs, where carbon dioxide passes into the alveoli to be exhaled.

10. Diaphragm • The diaphragm (pronounced: dye-uh-fram), which separates the chest from the abdomen, plays a lead role in breathing. • When we breathe out, the diaphragm moves upward, forcing the chest cavity to get smaller and pushing the gases in the lungs up and out of the nose and mouth.

11. Gases involved • The air we breathe is made up of several gases. Oxygen is the most important for keeping us alive because body cells need it for energy and growth. Without oxygen, the body's cells would die. • Carbon dioxide is the waste gas produced when carbon is combined with oxygen as part of the energy-making processes of the body. The lungs and respiratory system allow oxygen in the air to be taken into the body, while also enabling the body to get rid of carbon dioxide in the air breathed out.

12. Asthma • More than 20 million people in the United States have asthma, and it's the #1 reason that kids chronically miss school. • Asthma is a chronic inflammatory lung disease that causes airways to tighten and narrow. • Often triggered by irritants in the air such as cigarette smoke, asthma flares involve contraction of the muscles and swelling of the lining of the tiny airways. • The resulting narrowing of the airways prevents air from flowing properly, causing wheezing and difficulty breathing, sometimes to the point of being life-threatening. • Management of asthma starts with an asthma management plan, which usually involves avoiding asthma triggers and sometimes taking medications.

13. Fun facts • Each day, you breathe about 20,000 times, and by the time you're 70 years old, you'll have taken at least 600 million breaths. • We breathe 13 pints of air every minute. • More than half a liter of water per day is lost through breathing. • Yawning brings more oxygen to the lungs. • There is a sneeze record of 165 kilometers per hour. • Your right lung is slightly bigger then your left lung.

14. More Fun Facts • At rest, the body takes in and breathes out about 10 liters of air every minute. • The capillaries in the lungs would extend 1,600 kilometers if placed end to end. • A person at rest usually breathes between 12 to 15 times a minute. • The breathing rate is faster in children and women than in men, because the volume of the female & child lungs are smaller so more oxygen is needed and more CO2 needs to be exhaled out of the body. • People under the age of 30 take in double the amount of oxygen in comparison to an 80 year old.

15. citation "Google Images." Google Images. N.p., n.d. Web. 28 Aug. 2013. "Lungs and Respiratory System." TeensHealth. Ed. YaminiDurani, MD. Nemours, Oct. 2012. Web. 28 Aug. 2013.