The Respiratory System

The system of the body that deals with breathing The body takes in the oxygen that it needs and removes the carbon dioxide that it doesn’t

The Oxygen Delivery System Main function - to supply the blood with oxygen Does this through breathing

Breathing and Respiration are NOT the same thing!

Breathing Moving air in and out of the lungs

Respiration Chemical reaction that releases energy

Inhalation Breathing in Body gets oxygen from the air Rib muscles contract to pull ribs up and out Diaphragm muscle contracts to pull down the lungs Tissue expands to force (pull) in air.

Exhalation Breathing out Get rid of carbon dioxide Rib muscles relax Diaphragm muscle relaxes Tissue returns to resting position and forces (pushes) air out

Lungs Bronchial tubes Many smaller tubes Alveoli (alveolus) – surrounded by capillaries Average adult's lungs contain about 600 million of these air-filled sacs

Pathway of Oxygen Body breathes in the air which is pulled through the nose or mouth and down through the trachea

Pathway of Oxygen The trachea is a pipe shaped by rings of cartilage. It divides into two tubes called bronchi. Bronchi carry air into each lung.

Pathway of Oxygen Inside the lung, the tubes divide into smaller and smaller tubes called bronchioles. At the end of each of these tubes are small air sacs called alveoli. Capillaries, which are small blood vessels with thin walls, are wrapped around these alveoli.

Pathway of Oxygen Capillary walls are so thin and close to each other that the air easily diffuses through.

Pathway of Oxygen Oxygen diffuses through the capillaries into the bloodstream. Carbon dioxide in the bloodstream, diffuses through into the alveoli, and is then removed from the body when we breathe out.

The Diaphragm The muscle that controls the breathing process.

The Diaphragm The diaphragm flattens to cause the chest to expand and air is pulled into the lungs.

The Diaphragm When the diaphragm relaxes, the chest collapses and the air in the lungs is forced out.