Ch3 Sec5

Cell Division

Key Concepts

• What events take place during the three stages of the cell cycle?

• How does the structure of DNA help account for the way in which DNA copies itself?

Key Terms

• Cell cycle• Interphase• Replication• Mitosis• Chromosome• Cytokinesis

Ch3 Sec6

• Stage 1: Interphase– Growing– Copying DNA– Preparing for Division• Cell cycle: the regular sequence of growth and division

that cells undergo

Ch3 Sec6

• Stage 2: Mitosis– Is the stage during which the cell’s nucleus divides

into two new nuclei– During mitosis, one copy of the DNA is distributed

into each of the two daughter cells– Chromosomes are the threadlike chromatin in the

nucleus condenses to form double-rod structures

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• Stage 3: Cytokinesis– This completes the process of cell division– During cytokinesis, the cytoplasm divides. The

organelles are distributed into each of the two new cells

– Cytokinesis in Animal Cells– Cytokinesis in Plant Cells

Ch3 Sec6

• Structure and Replication of DNA– The structure of DNA– The Replication Process• Because of the way in which the nitrogen bases pair

with one another, the order of the bases in each new DNA molecule exactly matches the order in the original DNA molecule