Question

The small size of cells is best correlated with a. the fact that they are self-reproducing. b. an adequate surface area for exchange of materials. c. their vast versatility. d. All of these are correct.

Short answer

b. An adequate surface area for exchange of materials.

Step-by-step solution

Analyzing each option

: Option a: Cells being self-reproducing is an interesting fact, but it does not explain why cells are small. Option b: A small cell size provides a larger surface-to-volume ratio, which allows for efficient exchange of materials like nutrients, oxygen, and waste products. This option correlates well with the small size of cells. Option c: Although cell versatility is important, it does not explain why cells are small in size. Option d: This option would require all three other options to be valid correlations, but we have eliminated options a and c as explanations for the small size of cells.

Choosing the best correlated option

: From our analysis, it becomes clear that option b, "an adequate surface area for exchange of materials," is the best correlated with the small size of cells. Therefore, the answer to the exercise is: b. An adequate surface area for exchange of materials.

Key concepts

Surface Area to Volume Ratio

Cells are remarkably efficient at performing tasks essential to life due to their small size, which can be explained through the concept of the surface area to volume ratio. As an object, such as a cell, becomes smaller, the ratio of its surface area to its volume increases.
This high surface area to volume ratio is important because it maximizes the amount of area available for substances to diffuse across the cell membrane relative to the volume of the cell that those substances must nourish or cleanse. In simpler terms, smaller cells can move substances like nutrients and waste more efficiently across their cell membranes.

• A larger surface offers more space for the exchange processes.
• A smaller volume means the substance has less distance to travel within the cell.

Therefore, small cells are optimized for quick and effective transfer of materials, ensuring they maintain homeostasis and function properly.

Nutrient Exchange

Nutrient exchange is a crucial process for cellular life, allowing cells to obtain essential molecules and expel waste products. With a higher surface area to volume ratio, cells can efficiently manage these exchanges.
Diffusion is a common method by which nutrients move in and out of cells. This passive transport process does not require energy, instead relying on the movement of molecules from areas of higher concentration to lower concentration.

• Oxygen and glucose are absorbed by cells for energy production.
• Waste products like carbon dioxide are expelled to maintain cellular health.

Adequate nutrient exchange ensures cell vitality and supports various cellular activities, including metabolism and growth.

Cell Size

The size of a cell is a fundamental characteristic that influences how effectively it can perform its functions. Small cell size is directly related to the need for maintaining a favorable surface area to volume ratio.
Large cells encounter difficulties because their surface area does not increase as rapidly as their volume, limiting the efficient transfer of nutrients and waste. Conversely, small cells can sustain rapid nutrient exchange due to their high surface area relative to volume.
This is why biological organisms are composed of many small cells rather than a few large ones, maximizing their efficiency in various processes essential for life.

Efficiency in Transport Processes

Transport processes within a cell are vital for maintaining life functions, and cell size plays a significant role in their efficiency. Small cells, with their large surface area compared to volume, are better equipped to handle the demands of efficient transport.
Most cellular transport occurs across the cell membrane. This includes processes like:

• Active transport, which requires energy to move substances against their concentration gradient.
• Passive transport, where no energy is used, such as osmosis or simple diffusion.

The efficiency of these processes is crucial for the cell to interact with its external environment, enabling it to acquire nutrients and remove waste effectively. In summary, the small size of cells enhances their ability to efficiently control and regulate internal conditions by optimizing transport processes.