Download Digestive System

Respiratory System
In Class Notes:
Function of the Respiratory System
Provides oxygen for distribution to the
cells throughout your body. Also
removes carbon dioxide from the body.
Organs Involved: (30.5)
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Mouth: Air passage way (air is warm and moisture is added).
Nose: Same as above!
Pharynx (throat): Where passageways for air and food cross.
Epiglottis: Flap of tissue that momentarily covers the air pathway; prevents
water or food from entering.
Larynx (voice box): vocal cords vibrate as you exhale, producing sounds.
Trachea (windpipe): c-shaped rings of cartilage; fork into two bronchi.
Bronchi: tubes that connect trachea to lungs.
Lungs: exchange of oxygen and carbon dioxide with blood.
Bronchioles: small tubes at the end of bronchi
Alveoli: Gas exchange
Diaphragm: plays a key role in breathing; muscle that controls air pressure
in lungs.
How You Breathe
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You inhale through your nose (filters bacteria and dirt out of air by mucus or hair)
or mouth.
Next it passes into the pharynx (throat), where the air and food cross.
Passes through the open epiglottis, which blocks food from entering the lungs.
Then it goes through the larynx (voice box) and then into the trachea (windpipe)
The trachea splits into two bronchi (air tubes that connect the trachea to the lungs)
which then split into finer tubes called bronchioles.
Each bronchiole has a grapelike cluster of air sacs at the end of it called alveoli
(surface is covered with epithelial cells)
The oxygen you inhale dissolves into the epithelial cells
The oxygen diffuses into the web of capillaries and enters red blood cells. Carbon
dioxide goes from the capillaries across the epithelial cells and into he alveoli.
Then it is expelled up the trachea through the nose or mouth.
Diagram:
• Here are all the parts: (find a diagram you
like)
Parts you should know:
How is breathing regulated?
• Diaphragm controls the air pressure in lungsdiaphragm and rib muscles contract you
inhale.
• The level of carbon dioxide controls breathing.
What Can Smoking Do To You?
• Smoking can cause…
• Cancer
• Emphysema (when the walls of the alveoli lose their
elasticity)
• Higher risk for heart attack and strokes
• Higher cholesterol levels
• Heart has to work harder to deliver oxygen to cells
Name at least 3 disorders &
provide a description:
• Tuberculosis
Bacterial infection in the lungs
• Bronchitis
Inflammation of the inner lining of bronchial tubes
• Influenza
virus that infects the respiratory tract; fever, cough, soar throat,
headache, stuffy nose, muscle aches.