Respiratory System MHS

Why breathe?  CELLULAR RESPIRATION: sugar  energy  Sugar + Oxygen  Water + CO 2 + Energy  Need O 2 to turn nutrients  energy  CO 2 is a waste product.

Main parts of Respiratory System  Nasal Cavity  Pharynx  Larynx  Trachea  Bronchi / Bronchioles  Alveoli / Lungs

Role of the nasal cavity  The nasal cavity has: 1) CILIA: nose hairs to filter air. 2) CAPILLARIES: blood to warm the air 3) MUCOUS: filter and moisten air

The role of the pharynx  PHARYNX: a cross-over between the digestive tract and the respiratory system.  Air passes through the trachea.  Food passes through the esophagus.

The role of the larynx  Upper part of the trachea  the vocal folds.  When air goes past the folds, they vibrate, making sound.

The role of the trachea  Mucus in the trachea captures particles that escaped the nasal cavity’s filtration.  The cilia move the particles back to the pharynx where they are swallowed down the esophagus.

The role of the bronchi  The bronchi are lined with cilia and mucous glands.  These cilia perform the same function as the cilia in the trachea.

The role of the lungs  Lungs are filled with bronchioles, which divide into millions of alveoli.  The alveolus is surrounded by tiny blood vessels (called capillaries).  If more CO 2 in blood  into alveolus  If more O 2 in the alveolus  into blood.  Diffusion: moving from HIGH [ ]  LOW [ ]

Diffusion of gases between alveoli and capillary

How does Respiration take place? The goals of RESPIRATION are: 1) Take in O 2 from the air. 2) Take out CO 2 from the body:  Inspiration (inhaling)  Expiration (exhaling)

What happens when you inhale?  Diaphragm pulls down  Intercostal muscles tighten  Thorax gets bigger, making a vacuum (low P)  Oxygen rich air gets pulled into your lungs  Oxygen passes into your blood.

When you exhale  Muscles relax, the ribs fall in and down  Diaphragm moves up.  Volume of the thorax decreases, increasing pressure and pushing air out of the body.  CO 2 rich air leaves the blood and exits the body

Negative effects of air pollution. Air pollution can lead to:  Asthma  Allergies  Cancer  Fatigue

Negative effects of smoking  Deterioration of the respiratory system  Cardiovascular disease  Lung cancer  Shorter life expectency  Deterioration of quality of life  Impotance