Respiratory System• What is the main

role of the respiratory system?

• The respiratory system brings oxygen from the air into the body.

• It also removes the carbon dioxide (cellular waste) from inside the body.

Respiration• Breathing refers to

the process of inhaling and exhaling air from our lungs.

• Respiration is the process of chemical reactions that occur inside cells in the body.

• Respiration allows cells to release energy.

Body System Teamwork• The respiratory

system works in cooperation with the digestive and circulatory systems.

• The digestive system brings nutrients into the body.

• The respiratory system brings oxygen into your body.

• The circulatory system then takes the nutrients and the oxygen to your cells.

How Does Air Get To The Lungs?

• Air first travels into the body through the nose (or mouth).

• The nasal cavity contains mucus, which warms, moistens, and cleans the air we breathe.

• Inside of the nose are cilia, which are hair-like. They push the mucus back to the esophagus.

How Does Air Get To The Lungs?

• From the nasal cavity, air flows back through the pharynx (throat) and trachea (windpipe).

• The epiglottis is a small flap of tissue that closes when you swallow, sending food into the esophagus and not into the trachea.

How Does Air Get To The Lungs?

• After the trachea, the air moves into the left and right bronchi, within the lungs.

• The bronchi get smaller and smaller within the lungs until they reach tiny sacs at the very end.

• These structures are called alveoli.

Alveoli• Alveoli are tiny sacs

at the ends of the bronchi.

• There are over 300 million alveoli in the lungs.

• The alveoli are covered with capillaries.

• It is in the alveoli that the gas exchange takes place.

Alveoli & Gas Exchange

• Blood that is low in oxygen and full of carbon dioxide arrives at the alveoli.

• The carbon dioxide is then released from the blood into the alveoli, and exhaled from your body.

Alveoli & Gas Exchange

• At this same time, oxygen that is in the alveoli enters the bloodstream through the capillaries, to be taken back to the heart, then to the rest of the body.

• This is known as gas exchange.

Breathing• Our breathing is

controlled by a muscle called the diaphragm.

• When we inhale, the diaphragm contracts and flattens, allowing us to fill our lungs.

• When we exhale, our diaphragm relaxes, moving upward, causing the air to be pushed out of our lungs.

Smoking• No matter what anybody

tells you……. SMOKING KILLS YOU!

• Tobacco smoke contains tar, carbon monoxide, and nicotine.

• Each of these substances destroys your respiratory system!

Smoking• This is a picture of

two lungs.• The photo on the left

is that of a healthy lung.

• The photo on the right is the lung from a smoker.

• Imagine trying to get oxygen through there??

DON’T SMOKE