OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

What is the definition of photosynthesis?

1. A physical process for plant growth

2. A series of chemical reactions using sunlight to produce glucose

3. A method of water absorption in plants

4. A process of transporting nutrients

The correct answer is: A series of chemical reactions using sunlight to produce glucose

The definition of photosynthesis is accurately represented by the description of a series of chemical reactions using sunlight to produce glucose. This process primarily occurs in the chloroplasts of plant cells, where carbon dioxide and water are converted into glucose and oxygen, utilizing sunlight as an energy source. The glucose produced serves as a vital energy source for plants and is fundamental for growth and development. Additionally, oxygen released during photosynthesis is crucial for the respiration of most living organisms. In contrast, the other options do not encapsulate the core essence of photosynthesis. While plant growth involves many processes including nutrient uptake and water absorption, these do not define the photosynthesis process itself. Water absorption is specifically related to how plants take in moisture from the soil, and transporting nutrients refers to the movement of minerals and other compounds within the plant, which are secondary processes that support life but are not directly indicative of photosynthesis.