1. KEY CONCEPT Cells have distinct phases of growth, reproduction, and normal functions.

2. I can describe the stages of the cell cycle.
I can compare rates of division in different cell types.
I can identify factors that limit cell size.

3. The cell cycle has four main stages.
The cell cycle is a regular pattern of growth, DNA replication, and cell division.

4. The 4 main stages of the cell cycle are gap 1, synthesis, gap 2, and mitosis.
Gap 1 (G1): cell growth and normal functions
DNA synthesis (S): copies DNA
Gap 2 (G2): additional growth
Mitosis (M): includes division of the cell nucleus (mitosis) and division of the cell cytoplasm (cytokinesis)
Mitosis occurs only if the cell is large enough and the DNA undamaged.

5. Cells divide at different rates.
The rate of cell division varies with the need for those types of cells.
Some cells are unlikely to divide (G0).

6. Cell size is limited.
Volume increases faster than surface area.

7. Surface area must allow for adequate exchange of materials.
Cell growth is coordinated with division.
Cells that must be large have unique shapes.

8. In which stage of the cell cycle do the nucleus and its contents divide?
A. synthesis
B. gap 1
C. mitosis
D. gap 2

10. During the gap 1 stage of the cell cycle, a cell
a. splits into two new cells.
b. carries out its normal functions.
c. duplicates its DNA.
d. divides its cytoplasm.

11. Which of the following phrases best describes cytokinesis?
a. division of the cytoplasm
b. division of the nucleus
c. division of DNA
d. division of surface area

12. Which statement is true about the rates of cell division in eukaryotes?
A. They remain the same for the life of the organism.
b. They are faster than that of prokaryotes.
c. They increase with the age of the organism.
d. They vary greatly within an organism.

13. Which of the following limits the maximum size of a cell?
a. the stage of the cell cycle
b. the ratio of cell surface area to volume
c. the number of mitochondria in the cell
d. the size of the organism