Question
Define the following terms.
1. Respiration
2. Combustion
3. Photosynthesis
1. Respiration
2. Combustion
3. Photosynthesis
✓
Answer
1. Respiration – Respiration is a chemical process that takes place in all living organisms by which they take in oxygen and use it to break down food and release energy, carbon dioxide and water vapour.
2. Combustion – Combusion or burning is a chemical process in which substances combine with oxygen (of the air) and produce new substances called oxide along with energy in the form of heat and light.
3. Photosynthesis – Photosynthesis is the process by which green plants make their own food (in the form of carbohydrates) (from air) and water (absorbed from soil) in the presence of sunlight and with the help of chlorophyll.
2. Combustion – Combusion or burning is a chemical process in which substances combine with oxygen (of the air) and produce new substances called oxide along with energy in the form of heat and light.
3. Photosynthesis – Photosynthesis is the process by which green plants make their own food (in the form of carbohydrates) (from air) and water (absorbed from soil) in the presence of sunlight and with the help of chlorophyll.
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