THE RESPIRATORY SYSTEM

Main Function: Exchanges oxygen and

carbon dioxide between the blood, air & tissues

NOSE & MOUTH

1. Entryway for air2. Nasal hairs filter air3. Warm air before it travels to lungs

PHARYNX

1. Throat region;2. Common

pathway for air and food

EPIGLOTTIS

Flap that closes off the trachea when swallowing to prevent choking

up down

Animated web link tutorial

LARYNX

1. also called Voice box or Adam's apple;

2. contains vocal cords

TRACHEA

1. Also called the windpipe;

2. tube that carries air to lungs;

3. lined with cartilage rings to keep the trachea open

BRONCHI & BRONCHIOLES

1. Bronchi :Two smaller tubes that Branch off from trachea into each lung

2. Bronchioles: smaller tubes that branch out further into lung

ALVEOLI

Small air sacs responsible for exchanging gases with the blood

LUNGS

1. Have large surface area for gas exchange

2. Right lung has three lobes; left lung has only two lobes (heart takes up space on left side)

HEALTHY LUNG

EMPHYSEMA

LUNG CANCER

DIAPHRAGM

1. Muscular sheet under lungs that moves down as it contracts to bring air into the lung (INHALATION)

2. Air moves out of lung as diaphragm relaxes and moves upward (EXHALATION)

NOSE

EPIGLOTTISLARYNXBRONCHIOLES

ALVEOLI

TRACHEA

DIAPHRAGM

PHARYNX

BRONCHI

MOUTH

LUNGS

MECHANICS OF BREATHING

Tutorial Web link

How Breathing is Controlled

1. Can somewhat control breathing 2. When you do not have enough oxygen, your

chest begins to feel tight & throat burns3. Medulla oblongata causes muscles in diaphragm

& chest to contract & force air into lungs4. Cells in medulla oblongata sense the CO2

content; when it is too high, it will cause you to inhale