Limitations to cell size
The size of a cell is limited by the surface area-to-volume ratio, which affects the efficiency of transport processes. As a cell grows, its volume increases faster than its surface area, leading to a reduced surface area-to-volume ratio.
- Surface Area-to-Volume Ratio: A higher surface area-to-volume ratio allows for more efficient exchange of materials with the environment. Smaller cells or cells with specialised structures (like microvilli) can maintain a high ratio, facilitating effective nutrient uptake, waste removal and gas exchange.
- Rate of Diffusion: The rate of diffusion is affected by the surface area available for exchange. Larger cells with a low surface area-to-volume ratio may face challenges in efficiently exchanging materials due to longer diffusion distances. Therefore, cells often remain small or adopt shapes that optimise their surface area-to-volume ratio to support efficient metabolic activities and maintain cellular function.
