4. Why are cells so small?
• Most cells are less than 100µm (100x10^-6)
5. Ratio of surface area to volume
• Why is increased surface area so
important to cells?
– Transport
• More proteins
• Greater diffusion of substances
• Increased reaction rates
• Greater diffusion of waste material
– Cellular Communications
• Signaling proteins
6.
7. Cell
diameter
Cell 1:
0.00002m
Cell 2:
0.001m
Cell 3:
.025m
Cell 4:
.030m
Cell 5:
15m
Surface
area
.0000000025m 0.000006m
0.00375m .0054m
1350m
Volume
8.0 x 10^15 m 0.000000001m 0.000015625m
0.000027m 3375m
Surface
Area to
Volume
Ratio
312500:1 6000:1 240:1 200:1 2:5
Cell
diameter
Cell 1:
0.00002m
Cell 2:
0.001m
Cell 3:
.025m
Cell 4:
.030m
Cell 5:
15m
Surface
area
Volume
Surface
Area to
Volume
Ratio
8. G1: Gap 1; cell grows and
performs normal functions
S: synthesis; DNA is
replicated
G1: Gap 1; cell grows and
performs normal functions
9.
10. Main Ideas
• All living organisms are composed of
cells.
• Cells divide to increase their numbers
through a process of mitosis, which
results in two daughter cells with
identical sets of chromosomes.
13. Introduction
• Most cells in an organism go through a
cycle of growth, development, and division
• Goal: Grow, develop, replace old or
damaged cells, produce new cells
14. Introduction
• Most cells in an organism go through a
cycle of growth, development, and division
• Goal: Grow, develop, replace old or
damaged cells, produce new cells
15.
16.
17.
18. Interphase
THE CELL:
• grows to it’s mature size
• makes a _____ of its DNA
• prepares to _______ into two
cells
Copy
Divide
