Download bio p. 247 - Buena Regional High School

Biology p. 247 Section 9.1 Assessment
1.
Relate cell size to cell functions, and explain why cell size is limited.
As the cell size increases the cell’s ability to transport nutrients into and waste out of the cell
through the cell membrane becomes more difficult. Control of the cell by the nucleus also
becomes difficult.
2. Summarize the primary stages of the cell cycle.
Interphase (cell grows, metabolic functions, replicates DNA & prepares to divide); mitosis
(sorting and dividing nuclear material …chromosomes); cytokinesis (cytoplasm w/organelles
divides into two new daughter cells)
3. Describe what happens to DNA during the S stage of interphase.
The DNA (in chromatin form) replicates (copies itself) during the S stage of interphase.
4. Diagram the stages of the cell cycle and describe what happens in each.
5.
Hypothesize what the result would be if a large cell managed to divide, despite the fact that it
had grown beyond the optimum size.
If a big cell did divide its daughter cells would probably still be big also and not be able to sustain
(feed/clean) themselves if SA to V ratio was still too large. These new cells would probably not
survive.
6.
If a cube representing a cell is 5um on a side, calculate the surface area to volume ratios, and
explain why this is or is not a good size for a cell.
SA (l x w) x 6 sides
(5 x 5) = 25 x 6= 150 um2 ratio SA/V
V
5 x 5 x 5 = 125 um3
lxwxh
150/125 = 1.2
1.2 is not a very high ratio; this cell would have difficulty transport nutrients in and waste out
of the cell.