It is advantageous for cells to be small because:
a small cell size prevents a cell from weighing too much
a small cell size occupies less space in nature where space is limited
a small cell has a small volume relative to surface area, thereby increasing efficient transport
a small cell has a small surface area relative to volume, thereby facilitating ion balance
a small cell is better able to conserve energy than a larger cell.
The correct answer and explanation is :
The correct answer is:
“A small cell has a small volume relative to surface area, thereby increasing efficient transport.”
Explanation:
Cells remain small primarily due to the surface area-to-volume ratio (SA:V ratio), which plays a crucial role in maintaining efficient transport of materials. As a cell grows larger, its volume increases at a much faster rate than its surface area. This presents a challenge because the cell’s surface is responsible for exchanging gases, nutrients, and waste with the external environment.
Why is a high SA:V ratio important?
- Efficient Nutrient and Waste Exchange:
A small cell allows for a high SA:V ratio, meaning that nutrients (such as oxygen and glucose) can quickly enter the cell, while waste products (such as carbon dioxide and urea) can be efficiently expelled. If the cell were too large, diffusion would take too long to sustain cellular functions, leading to inefficiencies or cell death. - Faster Transport Mechanisms:
Cellular processes such as diffusion, osmosis, and active transport work best when the distance to the cell’s center is short. A smaller volume ensures that molecules do not have to travel long distances to reach organelles, making metabolic reactions more effective. - Cell Communication and Signaling:
In multicellular organisms, cells communicate using chemical signals. A smaller cell allows these signals to travel quickly to regulate cellular activities, maintaining homeostasis. - Energy Efficiency and Division:
Smaller cells can divide more easily and frequently, allowing for rapid growth and tissue repair in organisms. This division also prevents cells from becoming too large, which could cause difficulties in sustaining life processes.
In summary, a small cell size maximizes efficiency by maintaining a high surface area-to-volume ratio, facilitating faster and more effective transport of substances.