DO NOW: Describe what you think happens when you are choking. Aim : What is the Respiratory System and why is it important for maintaining Homeostasis?

What is the respiratory system? The respiratory system has 2 main functions: Take in OXYGEN from the outside (INHALE) To get rid of CARBON DIOXIDE from the inside (EXHALE)

The parts of the respiratory system The respiratory system extends from the head to the chest. It begins in the head where air enters and exits through the nose and mouth.

The parts of the respiratory system (continued 1) Once the air passes through the mouth, it enters the pharynx (the back of the throat). Once passed the pharynx, the air enter a rigid (stiff) tube called the trachea.

The parts of the respiratory system (continued 2) The trachea is made up of cartilage which makes it stiff. The trachea is lined with cilia and mucus. This helps to keep foreign material out of the lung. Foreign material sticks to the mucus and the cilia pushes the material up into your pharynx where you can cough it up or swallow it.

The parts of the respiratory system (continued) At the end of the trachea, it slips into two separate smaller tubes called the bronchi The bronchi enters a soft, sponge organ called the lungs

The parts of the respiratory system (continued 3) Once in the lungs, the bronchi further reduce (get smaller) and branch into Bronchioles. At the end of the bronchioles there are a cluster of sacks called alveoli. The alveoli is the place where gas exchange occurs.

CO2 diffuses into the alveoli O2 diffuses into the red blood cell The alveoli is a thin walled chamber that is surrounded by capillaries. This is where gases exchange from outside the body to the inside the body and vise versa. This process is possible because of the different concentration of gases inside and outside the body. Alveoli Deoxygenated blood side Oxygenated blood side CO2 diffuses into the alveoli O2 diffuses into the red blood cell Capillary

How do we breathe? The lungs do not have muscles. The lungs are enclosed in a vacuumed chamber (cavity) The diaphragm is a muscular membrane that contracts and expands causing the cavity it enlarge and shrink , which makes the lungs inhale and exhale. http://www.youtube.com/watch?v=Na-ZvufXwng&feature=related http://www.youtube.com/watch?v=f2G6_otEto4&feature=related

One way in, one way out Because the respiratory system only has one entrance and exit point, anything blocking the pathway will interrupt gas exchange (choke). Since oxygen cannot reach the alveoli, no oxygen can go into the blood. If no oxygen gets into the blood, the body cell will not be able to perform cellular respiration in the cells.

What happens when we exercise? When you exercise, your body works more. Because your body is working harder, it needs more energy. Because the body needs oxygen to break down glucose for energy (respiration), you start to breath faster. Because you need the oxygen fast, your heart pumps faster.

What happens when we exercise? (continued 2) As the glucose is converted into energy, Carbon Dioxide is released. This carbon dioxide is diffused into the blood. The blood brings the carbon Dioxide to the lungs. The carbon dioxide is expelled as you exhale More work More Oxygen & Carbon Dioxide

Pharnyx Mouth Trachea Bronchi Bronchiole Alveoli