Overview and Objectives

This lesson describes the chemical structure of DNA and how the structure relates to genes and chromosomes. The replication of DNA prior to cell division to create the chromatids of replicated chromosome is illustrated, showing how the main DNA replicating enzymes work together in living cells.

At completion of this lesson you should be able to:

1. Detail the molecular nature of a gene.
2. Recognize when and where replication of the DNA that is packaged in an organism’s chromosome is happening for growth, maintenance, and reproduction.
3. Describe how chromosome replication speed can be increased with multiple origins of replication and bidirectional replication.
4. Explain the role of each of the primary DNA replicating enzymes in conducting replication of a chromosome.  Include the role of these enzymes in ensuring the accuracy of the replication process.
5. Predict how the semiconservative replication of a double stranded DNA will proceed given the structure of the molecule and the specific function of the DNA replicating enzymes.