Which of the following parameters is most likely to limit the maximum size of a cell?

• A. The number of mitochondria
• B. The surface area-to-volume ratio
• C. The amount of DNA in the nucleus
• D. The concentration of ribosomes

Answer: (B)

Verified step by step guidance

1. Understand the problem: The question is asking which parameter limits the maximum size of a cell. This involves understanding the relationship between cell size and its functional constraints.
2. Recall the concept of surface area-to-volume ratio: As a cell grows larger, its volume increases faster than its surface area. This ratio is critical because the surface area determines the cell's ability to exchange materials (e.g., nutrients, waste) with its environment, while the volume represents the cell's metabolic demands.
3. Analyze the options: Evaluate each parameter in the context of cell size. For example, the number of mitochondria or ribosomes can increase as the cell grows, and the amount of DNA in the nucleus is not directly related to cell size. However, the surface area-to-volume ratio imposes a physical limitation on how large a cell can grow while maintaining efficient exchange of materials.
4. Connect the concept to the correct answer: The surface area-to-volume ratio is the most likely parameter to limit cell size because it directly impacts the cell's ability to sustain itself. A low ratio in larger cells would hinder the exchange of essential substances, leading to inefficiency.
5. Conclude: The correct answer is 'The surface area-to-volume ratio,' as it is the primary factor that limits the maximum size of a cell due to its impact on material exchange and metabolic efficiency.