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Biology Question and Answer
❖ Question:
Explain the process of photosynthesis and its importance for life on Earth.
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✅ Answer:
Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy, usually from the sun, into chemical energy stored in the form of glucose (a type of sugar). This process takes place mainly in the chloroplasts of plant cells, where the green pigment chlorophyll absorbs sunlight.
The overall chemical reaction can be summarized as:
6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂
This means that carbon dioxide (CO₂) from the air and water (H₂O) absorbed by roots are converted into glucose (C₆H₁₂O₆) and oxygen (O₂) with the help of sunlight.
Steps in Photosynthesis:
1. Light Absorption: Chlorophyll absorbs sunlight, which excites electrons and starts the process.
2. Water Splitting: Water molecules are broken down to release oxygen and hydrogen ions.
3. Carbon Fixation: Carbon dioxide is combined with hydrogen to form glucose.
4. Energy Storage: Glucose is stored and used by the plant as energy for growth and development.
Importance of Photosynthesis:
1. Source of Food: It produces glucose, which is the primary source of energy for plants and indirectly for other organisms.
2. Oxygen Production: It releases oxygen into the atmosphere, which is essential for the survival of humans and animals.
3. Carbon Cycle: It helps reduce carbon dioxide levels, controlling the Earth’s climate and supporting life.
4. Basis of Ecosystems: Photosynthesis forms the foundation of the food chain, supporting herbivores and, subsequently, carnivores.
In conclusion, photosynthesis is a fundamental process that sustains life on Earth by providing food, oxygen, and maintaining ecological balance.
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