The main components that cause air to go in and out of the lungs are the diaphragm and rib muscles. When you inhale, the diaphragm contracts and moves downward, and the rib muscles expand the rib cage outward and upward. This increases the volume of the chest cavity and causes the lungs to expand and draw air in through the airways. When you exhale, the diaphragm and rib muscles relax and move in the opposite direction, decreasing the chest cavity volume and causing the lungs to expel air out through the airways.

1. RESPIRATORY SYSTEM
IMPORTANT POINTS

2. Nasal Cavity
Nose
Mouth
Bronchus
Bronchiole
Alveolus
Diaphragm
Throat
(pharynx)
Windpipe
(Trachea)
Left lungs
Ribs
PARTSOFTHE
RESPIRATORYSYSTEM

3. AIR PATHWAY
Nose/
Nostrils Nasal
cavity
Pharynx/
Throat
Trachea/
Windpipe
BronchiBronchioles
Alveoli/
air sacs
Mouth/ Oral
Cavity
Larynx/
Voicebox

4. BREATHING MECHANISM
TYPE OF
BREATHING
ORGAN
Inhalation
(air
enters)
Exhalation
(air exits)
LUNGS Expands Contracts
DIAPHRAGM Goes
downward
contracts
Goes upward
relaxes

5. IMPORTANT POINTS
1. THE NOSE FILTERS AND WARMS THE ENTERING AIR.
2. AIR ENTERS THE NOSE OR MOUTH, GOES DOWN THE
TRACHEA AND BRONCHUS, AND ENDS IN THE
ALVEOLI.
3. GASES ARE EXCHANGED AT THE ALVEOLI.
4. THE DIAPHRAGM AND RIB MUSCLES WORK TOGETHER
TO EXPAND AND CONTRACT THE SIZE OF THE CHEST

6. 5. BREATHING IS THE MECHANICAL PROCESS OF
PUMPING AIR INTO AND OUT OF THE LUNGS.
6. THE GAS THAT WE TAKE (INHALE) IS OXYGEN AND
THE GAS THAT WE BREATHE OUT (EXHALE) IS CARBON
DIOXIDE.
7. THE CHEMICAL PROCESS IN WHICH OXYGEN AND
CARBON DIOXIDE ARE EXCHANGED BETWEEN THE
OUTSIDE AIR AND THE CELLS IS CALLED RESPIRATION.

7. MULTIPLE CHOICE
QUESTION
1. THE MAIN FUNCTION OF THE RESPIRATORY
ORGAN SYSTEM IS ___________BETWEEN THE
ORGANISM AND THE ENVIRONMENT.
A. GAS EXCHANGE
B. TAKING IN OXYGEN
C. CONTROL BREATHING
D. FILTER AIR

8. MULTIPLE CHOICE
QUESTION
2. WHEN YOU HOLD YOUR BREATH, WHICH OF THE
FOLLOWING FIRST LEADS TO THE URGE TO BREATHE?
A. FALLING CO2
B. FALLING O2
C. RISING CO2
D. RISING PH OF THE BLOOD

9. MULTIPLE CHOICE
QUESTION
3. WHEN YOU INHALE, THE DIAPHRAGM
A. RELAXES AND MOVES UPWARD
B. RELAXES AND MOVES DOWNWARD
C. CONTRACTS AND MOVES UPWARD
D. CONTRACTS AND MOVES DOWNWARD

10. MULTIPLE CHOICE
QUESTION
4. WHERE DOES EXCHANGE OF GASES TAKE PLACE?
A. ALVEOLI
B. BRONCHIOLES
C. BRONCHI
D. DIAPHRAGM

11. MULTIPLE CHOICE
QUESTION
5. THE CHEMICAL PROCESS IN WHICH OXYGEN AND
CARBON DIOXIDE ARE EXCHANGED BETWEEN THE OUTSIDE
AIR AND THE CELLS IS CALLED
A. BREATHING
B. EXHALING
C. INHALING
D. RESPIRATION

12. WRITE IN COLUMN B THE CORRECT
SEQUENCE OF THE AIR PATHWAY IN THE
RESPIRATORY SYSTEM.

13. ANSWER THE QUESTION FOR 3 POINTS.
WHAT CAUSE THE AIR TO GO IN AND OUT OF
YOUR LUNGS?