AP BIOLOGY

CELL DIVISION

THE CELL CYCLE

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
How does the surface area/volume ratio change as the size of the cell increases?
A
It increases
B
it decreases
C
it remains the same
D
it is not affected by cell size
Explanation: 

Detailed explanation-1: -As the radius of a cell increases, its surface area increases as the square of its radius, but its volume increases as the cube of its radius (much more rapidly). Therefore, as a cell increases in size, its surface area-to-volume ratio decreases.

Detailed explanation-2: -Cell growth causes the surface area to volume ratio to decrease. This is because, as a cell grows, the volume of the cell (its internal contents) increases faster than its surface area (its cell membrane).

Detailed explanation-3: -As cells grow larger, the ratio of surface area to volume decreases dramatically, just like in your agar cubes. Larger cells must still transport materials across their membranes, but have a larger volume to supply and a proportionately smaller surface area through which to do so.

Detailed explanation-4: -Graphs of surface area, A against volume, V of the Platonic solids and a sphere, showing that the surface area decreases for rounder shapes, and the surface-area-to-volume ratio decreases with increasing volume.

There is 1 question to complete.