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

How do plants use glucose to aid in growth?

1. To generate chlorophyll exclusively

2. To form cellulose for cell walls and proteins

3. To store energy solely for winter

4. To absorb more sunlight

The correct answer is: To form cellulose for cell walls and proteins

Plants use glucose primarily as a fundamental building block for growth and development, particularly in forming cellulose for cell walls and synthesizing proteins. Glucose, produced through photosynthesis, serves as a vital source of energy and a precursor for various organic compounds. Cellulose, a key structural polysaccharide, is composed of long chains of glucose molecules. It provides rigidity and strength to plant cell walls, enabling plants to maintain their structure and withstand various environmental pressures. Without sufficient glucose, a plant would struggle to produce cellulose, leading to impaired growth and development. Additionally, glucose is involved in the synthesis of proteins through a series of biochemical processes. Proteins are crucial for numerous functions in plants, including enzyme activities, signaling, and transport. Hence, the role of glucose is not limited to energy storage or specific seasonal use; instead, it is integral to the overall growth process of the plant. The other options refer to aspects that do not accurately represent the comprehensive role of glucose in plant growth. For instance, generating chlorophyll is primarily reliant on other compounds; storing energy solely for winter neglects the continuous energy needs of the plant throughout its life cycle; and absorbing more sunlight relates to the plant's structure and adaptations rather than glucose utilization specifically.