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Cambridge IGCSE Biology Fourth Edition
Respiration and Gas Exchange
Chapter No. 1, Page No.
1. What is aerobic respiration?
Ans. Aerobic respiration is breaking down of glucose or food molecules to
produce energy in the absence of oxygen.
2. What is anaerobic respiration?
Ans. Anaerobic respiration is breaking down of glucose or food molecules
in the presence of oxygen.
3. What is gas exchange?
Ans. Gas exchange is the diffusion of oxygen and carbon dioxide into and
out of an organism's body.
4. What is the gas exchange surface?
Ans. The gas exchange surface is a part of the body where gas exchange
between the body and the environment takes place.
5. What is the alveoli?
Ans. In the alveoli, oxygen diffuses into the blood, so the surface of the
alveoli is the gas exchange surface. Because they are so full of air spaces,
lungs feel very light and spongy to touch.
6. What is the trachea?
Ans. Trachea is the tube through which air travels to the lungs; it has rings
of cartilage in its walls to support it.
7. What are the goblet cells?
Ans. The goblet cells are the cells found in the lining of the respiratory
passages and digestive system, which releases mucus.
8. What is the cilia?
Ans. The cilia are tiny projections from some of the cells in the lining of the
respiratory passages. The cilia of many adjacent cells beat rhythmically in
the unison.
9. What is the thorax?
Ans. The thorax is the upper part of your body from the neck down to the
bottom of the ribs and diaphragm. In the thorax, the trachea divides into