Question

The cells of an ant and an elephant are, on average, the same small size; an elephant just has more of them. What is the main advantage of small cell size? (Explain your reasoning.)

a. A small cell has a larger plasma membrane surface area than does a large cell.
b. Small cells can better take up sufficient nutrients and oxygen to service their cell volume.
c. It takes less energy to make an organism out of small cells.
d. Small cells require less oxygen than do large cells.

Answer 1

Small cells are more efficient at nutrient uptake and waste removal due to a higher surface area-to-volume ratio, which facilitates better diffusion and transport of substances across the cell membrane.

Step-by-step explanation:

The main advantage of small cell size is that small cells can better take up sufficient nutrients and oxygen to service their cell volume. This is mainly due to the surface area-to-volume ratio increasing as cells get smaller. As the radius of a cell increases, while its surface area increases as the square of the radius, its volume increases even more rapidly, as the cube of the radius.

Consequently, a large cell would have a lower surface area relative to its volume, which would be less efficient for diffusion and transport of substances. The larger the cell, the harder it would be for the cell membrane to support the required rate of diffusion for the increased volume. Therefore, smaller cells are more efficient at nutrient uptake and waste removal.