CIE iGCSE Co-Ordinated Science B6.1 Photosynthesis Exam Style Questions Paper 1
▶️ Answer/Explanation
In the diagram, part D is the chloroplast, which contains chlorophyll. Photosynthesis occurs in chloroplasts, where light energy is absorbed to convert carbon dioxide and water into glucose and oxygen. The cell wall (A) provides support, cytoplasm (B) is where metabolic reactions occur, and the nucleus (C) controls cell activities. Therefore, the correct answer is D.
✅ Answer: (D)
✅ Answer: (D)
▶️ Answer/Explanation
Photosynthesis is the process by which plants synthesise carbohydrates from raw materials using energy from light. The raw materials are carbon dioxide and water, and the products are glucose and oxygen. Therefore, option B correctly states that a plant uses carbon dioxide and water to produce glucose and oxygen.
✅ Answer: (B)
✅ Answer: (B)
▶️ Answer/Explanation
Palisade mesophyll cells are the main site of photosynthesis in a leaf. They are found in the upper part of the leaf and contain many chloroplasts, which are the organelles responsible for converting light energy into chemical energy (glucose) during photosynthesis. Phloem transports sucrose and amino acids, xylem transports water and mineral ions, and spongy mesophyll is involved in gas exchange with fewer chloroplasts. Therefore, palisade mesophyll cells produce the most glucose.
✅ Answer: (A)
✅ Answer: (A)
▶️ Answer/Explanation
A variegated leaf has both green areas (containing chlorophyll) and white areas (lacking chlorophyll). By testing the leaf for starch (using iodine solution) after exposing it to light, you can compare the green and white areas. The green areas will test positive for starch (showing that photosynthesis occurred), while the white areas will test negative (showing no photosynthesis occurred). This proves that chlorophyll is necessary for photosynthesis.
A completely green leaf cannot be used for this test because it has chlorophyll throughout, so you cannot compare areas with and without chlorophyll. Carbon dioxide, light, and water can all be tested using a completely green leaf by controlling the supply of each factor.
✅ Answer: (B)
▶️ Answer/Explanation
In the diagram, part D is the chloroplast, which contains chlorophyll. Photosynthesis occurs in chloroplasts, where light energy is absorbed to convert carbon dioxide and water into glucose and oxygen. The cell wall (A) provides support, cytoplasm (B) is where metabolic reactions occur, and the nucleus (C) controls cell activities. Therefore, the correct answer is D.
✅ Answer: (D)
✅ Answer: (D)