Respiratory System In Class Notes:

Function The function of the circulatory system is to transport nutrients, oxygen, and hormones throughout the body Also, the circulatory system carries waste away from the body.

Organs Involved Nose/Mouth- air enters respiratory system Pharynx- chamber in upper throat where air passes Epiglottis- flap of tissue that momentarily covers the air pathway and prevents water or food from entering Larynx- voice box and air pathway Trachea- air pathway AKA windpipe Bronchi- connects trachea to lungs Lungs- exchanges oxygen and CO2 with the blood Bronchioles- thin tubes that branches from the bronchus within the lungs Alveoli- tiny air sac Diaphragm- a sheet of muscle that plays a key role in breathing

Sequence of breathing: INHALING –Diaphragm and ribs contract –Fill up lungs with air EXHALING -diaphragm and ribs relax -air rushes from lungs out of nose or mouth

Diagram:

Parts you should know:

How is breathing regulated? Breathing is regulated by the medulla in the brain. The medulla increases the breathing rate when the CO2 level is too high. When the body is a rest or does not require high levels of oxygen the rate of breathing slows.

What effects does smoking have on the respiratory system? Smoking exposes the respiratory system to many harmful substances. These substances can: –Destroy cilia –Increase risk of lung cancer –Increase risk for other respiratory diseases

Name at least 3 disorders & provide a description: Asthma: disease affecting the airways that carry air to and from lungs Aortic aneurysms: weakened bulging areas in the aorta Stroke: if a clot forms in an artery leading to the brain a stroke can occur