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Question: As the size of the cell increase A. The total surface of area decreases at the same rate as the vo...

As the size of the cell increase
A. The total surface of area decreases at the same rate as the volume
B. The volume increases at the same rate as the total surface area
C. The total surface area increase faster than the value
D. The volume increases faster than the surface area

Explanation

Solution

As a cell grows bigger, its internal volume enlarges and the cell membrane expands.

Step by step answer: Surface area to volume ratio, in simply means the size of surface area to the volume of substance that can pass through it at a particular time. Amoeba and some bacterias are flat and have a large surface area to volume ratio. Whereas humans have a small surface area volume so diffusion is very slow or does not take place at all.
When the cell increases in size, the volume increases faster than the surface area, because the volume is cubed where surface area is squared.
For a single-celled organism (or a cell in a multicellular organism’s body, for that matter), the surface is a critical interface between the organism.
Changes in the surface area to volume ratio have important implications for limits or constraints on organism size and help explain some of the modifications seen in larger-bodied organisms. Exchange of materials often occurs through the process of diffusion, in which dissolved molecules or other particles move from areas of higher concentration to areas of lower concentration (although some exchange is mediated by cellular mechanisms). This type of exchange is a passive process, and as a result, imposes constraints upon the size of a single-celled organism or cell. Materials must be able to reach all parts of a cell quickly, and when the volume is too large relative to the surface area, diffusion cannot occur at sufficiently high rates to ensure this.
Organisms exhibit a variety of modifications, both physiological and anatomical, to compensate for changes in the surface area to volume ratio associated with size differences.
This is actually why cells divide. When they become too large and it takes too long for them to transport materials across the cell, they lose efficiency and divide in half to raise the surface area to volume ratio.
Hence option C is correct.

Note: One example of this is the higher metabolic rates found in smaller (homeothermic) animals. Because of their large surface area relative to volume, small animals lose heat at much higher rates than large animals, and therefore must produce more heat to offset the effects of thermal conductance.