Correct Option
The correct option is 1 only
Explanation
Autotrophic nutrition involves the synthesis of organic food (carbohydrates) from inorganic raw materials like carbon dioxide and water, in the presence of sunlight and chlorophyll. This process is known as photosynthesis.
Statement-wise Analysis
- Statement 1 is Correct: In autotrophs (green plants), carbohydrates produced through photosynthesis provide energy for the plant's metabolic activities. The carbohydrates that are not utilized immediately are stored in the form of starch, which serves as an internal energy reserve.
- Statement 2 is Incorrect: Humans are heterotrophs. In the human body, the energy derived from the food consumed is stored in the form of glycogen, not starch. Starch is the storage polysaccharide of plants, whereas glycogen is the storage polysaccharide of animals.
- Statement 3 is Incorrect: Chlorophyll is the green pigment present in chloroplasts that is essential for photosynthesis. It traps solar energy, which is then used to convert carbon dioxide and water into carbohydrates. Without chlorophyll, autotrophic carbohydrate formation cannot occur.
Key Takeaway
Key Takeaway: Plants store excess energy as starch, whereas animals (including humans) store energy as glycogen. Chlorophyll is indispensable for autotrophic nutrition.