Module 7 Lesson 2 - 5

Lesson Summary

DNA replication is complex, and sometimes mistakes are made. Based on your knowledge of DNA structure and the many steps involved in replication, how do you think these mistakes could be made? Could these mistakes accumulate as you age? Lesson 4 explores these mistakes in more detail.

You now understand how the structure of DNA has led directly to its ability to be copied and passed to the new cells during cell division. The double-stranded DNA can unwind and serve as two template strands. New strands of DNA form to complement these template strands. Two new, identical molecules of DNA result.  Because an original strand of DNA is in each new DNA molecule, the process is considered semi-conservative.

In this lesson, you studied four important enzymes and how they function in DNA replication. You learned the difference between the leading strands and lagging strands and how elongation differs on each of these strands. Throughout this lesson, you were asked to think about where errors could occur to cause mistakes in DNA replication. In Lesson 4, these mistakes are discussed in more detail.

In the next lesson, you will see how the DNA structure codes for and is used to build proteins that our cells and bodies use in various structures and to fulfill various functions. Do not confuse the process of DNA replication you studied in this lesson with the process of translation to be discussed in Lesson 3.