Question

As a cell increases in size, the surface area and volume increase, but the surface area: volume ratio decreases?

1) surface area increases as the volume decreases.
2) surface area, volume and surface area volume ratio increases.
3) surface area and volume increase, but the surface area: volume ratio decreases.
4) surface area and volume decreases the surface area: volume ratio increases.

Answer 1

As a cell increases in size, its surface area-to-volume ratio decreases due to the volume increasing at a faster rate than the surface area.

Step-by-step explanation:

As a cell increases in size, its surface area-to-volume ratio decreases. This is because the surface area increases as the square of the radius, while the volume increases as the cube of the radius. Therefore, as the cell grows, its volume increases at a faster rate than its surface area, leading to a decrease in the surface area-to-volume ratio.

For example, in Figure 4.7, the cell on the left has a volume of 1 mm³ and a surface area of 6 mm², resulting in a surface area-to-volume ratio of 6 to 1. In contrast, the cell on the right has a volume of 8 mm³ and a surface area of 24 mm², resulting in a surface area-to-volume ratio of 3 to 1.