Organs
Which organ carries air from the throat to the lungs?
Trachea
What happens to the chest cavity during inhalation?
It expands
Where does gas exchange take place in the lungs?
Alveoli
What happens to the airways during an asthma attack?
They become inflamed, narrowed, and filled with extra mucus, making it hard to breathe
What are the tiny air sacs in the lungs where gas exchange happens?
Alveoli
During exhalation, what happens to the diaphragm?
It relaxes and moves upward
Why do alveoli have thin walls?
So gases (oxygen and carbon dioxide) can diffuse quickly.
Why do people with emphysema get short of breath?
Alveoli walls are damaged = fewer, larger sacs = less surface area for oxygen to diffuse.
Name the main muscle that helps you breathe
Diaphragm
Why do people breathe faster during exercise?
Muscles need more oxygen and produce more carbon dioxide. Faster breathing increases oxygen intake and carbon dioxide removal.
Why do alveoli have a large surface area?
To allow more oxygen to diffuse into blood at once.
Compare inhaled air and exhaled air in terms of oxygen and carbon dioxide
Inhaled = high oxygen, low carbon dioxide
Exhaled = lower oxygen, higher carbon dioxide
Which parts of the respiratory system branch off from the trachea into each lung?
Bronchi
If the diaphragm was damaged, why would it be hard to breathe?
The diaphragm is the main muscle for ventilation. Without it, air cannot be pulled in and pushed out efficiently.
Explain why diffusion depends on a concentration gradient.
Gases move from high to low concentration. Oxygen moves from alveoli (High) to blood (low), CO2 moves from blood (high) to alveoli (low)
What role do cilia and mucus in the trachea play?
Trap dust and germs. Cilia move mucus upward to be swallowed or coughed out.