This presentation includes the parts and function of respiratory system suited for Grade 9 - Science.

1. Respiratory
System

2. Breathing
• Process of drawing air into the lungs
(inhalation) and its corresponding
expulsion (exhalation).
• During inhalation, oxygen enters the
lungs and during exhalation, carbon
dioxide exits the lungs.

3. Parts of Respiratory System
• Nose
• Pharynx
• Larynx
• Trachea
• Bronchi
• Bronchial trees
• Bronchioles
• Lungs
• Air sacs/Alveoli
• Diaphragm

4. Parts of Respiratory SystemNose
Bronchi
Lungs
Trachea
Bronchial
trees
Air sacs
Diaphragm
Pharynx
Larynx
Bronchioles

5. Nose
• Gateway of the respiratory
system.
• Cilia- hairs that trap foreign
materials unnecessary for lungs.
• Mucous Membranes- moisten the
air before it enters.

6. Pharynx or Throat
• Narrow space located right
after the mouth and the nose.
• Nasopharynx- part of the
pharynx that is related to
respiration.

7. Larynx or Voice Box
• Organ that connects pharynx
and trachea.
• It contains vocal chords that
produce sounds when vibrated
by the air.

8. Trachea
• Narrow and cylindrical tube.
• 5 inches long.
• Passageway of air going in and
out the lungs.

9. Bronchi, Bronchi trees,
Bronchioles
• Bronchi- trachea splits into two
bronchi which insert to the lungs.
• Bronchi Trees- subdivision of
bronchi inside the lungs.
• Bronchioles- connected to air sacs.

10. Air Sacs
• Functioning system of lungs.
• Alveoli- inhaled oxygen passes
through it and then diffuses into
capillaries.

11. Lungs
• Cone-shaped organs.
• Pleura- two-layered membrane
that covers the lungs.
• Hilum- slit like opening in the lungs
where bronchi are inserted.

12. Diaphragm
• Sheet of smooth muscle located
below the lungs.
• It works with lungs during
breathing process.