1. Give 2 reasons why cells divide.
a. DNA overload – Too many demands on DNA
b. Exchanging materials – The bigger the cell,
the greater the distance oxygen, nutrients, &
waste have to travel for cell to work.
oxygen
oxygen
oxygen
Carbon
dioxide
Carbon
dioxide
Carbon
dioxide
2. How is a cell’s DNA like the books in
a library?
• DNA is like a book of instructions for a cell.
• The bigger the cell, the more demands there will be on
the DNA.
• The bigger the town/city, the more demands there will be
for a library book.
Instruction
Book
3. As a cell increases in size, which
increases more rapidly, its surface area or
its volume?
• volume
4. Calculate the surface area, volume, and ratio of surface area
to volume of an imaginary cubic cell measuring 4 cm on each
side.
Surface Area = 4 cm x 4 cm x 6 = 96 cm2
Volume = 4 cm x 4 cm x 4 cm = 64 cm3
4 cm
SA : V = 96:64 = 3:2
4 cm
4 cm
Connecting Concepts. Select 2 cell organelles and
describe how their functions might be impaired if the
cell were to become too large.
• Nucleus wouldn’t be able to control all cell activities if cell got too big.
• Ribosomes wouldn’t be able to make enough proteins for cell if cell got too
big.
• Mitochondria wouldn’t be able to supply enough energy/power for cell if
cell got too big.
• Endoplasmic reticulum wouldn’t be able to make enough lipids and
proteins if cell got to big.