The respiratory system allows for gas exchange in the body. It begins with the nostrils, where air enters and exits the nasal cavity to be warmed. The pharynx and larynx allow air to pass to the trachea and then bronchi, where air flows into the lungs. The lungs, located in the chest, have lobes and facilitate breathing, respiration, and protection from infection. Inhalation draws oxygen into the lungs through muscle contraction and exhalation removes carbon dioxide as a waste product.

2. Respiratory System
• It is a system that consist of organs and
structures used for the process of
respiration in an organism
• Involved in the intake and exchange of
oxygen and carbon dioxide
• Gas exchange
• Immunity functions

4. Nostril
• It is the part of the respiratory system in
which the air enters into and exits from
the body

5. Nasal Cavity
• A large air-filled space above and behind
the nose in the middle of the face
• The air passing the nasal cavity is warmed
within 1 degree of the body temperature
• Cilia – removes dusts and pathogens from
the air as it flows through the nasal cavity

7. Pharynx
• It is part of the throat that is behind the
mouth and nasal cavity and above the
esophagus and the larynx
• A tubular structure that allows the air to
pass through from the nose to the lungs
• Nasopharynx – upper portion of the
pharynx that is behind the nose and
surrounded by muscles that can continue
the respiratory function

9. Larynx
• Commonly known as the “voice box”
• Sounds are generated in the larynx; where
pitch and volume are manipulated
• Prevention of foreign objects from
entering the lungs by coughing out

12. Trachea
• Also called as the “windpipe”
• A cartilaginous tube that connects the
pharynx and the larynx to the lungs
• Passageway of air
• 10-16 centimeters in length

14. Bronchi
• Airway in the respiratory tract that
conducts air into the lungs
• Right Main Bronchus – wider, shorter and
more vertical than the left bronchus. It
enters in the right side of the lung
• Left Main Bronchus – longer than the right
bronchus. It enters in the left side of the
lung

16. Lungs
• Primary organs of respiration in humans
• Located in the chest on either side of the
heart in the rib cage
• Right Lung – has 3 lobes
• Left Lung – has 2 lobes
• Its function are breathing, respiration and
protection from infection

20. Inhalation
• Drawing in oxygen into the lungs
• It is a vital process in human life
• Contraction of muscles in the rib cage; this
causes the expansion of the chest cavity
• Contraction of the diaphragm

22. Exhalation
• Flow of the air out of the organism
• The main reason of exhalation is to get rid
of the carbon dioxide, which is a waste
product of the gas exchange, inside the
body