DNA replication - shaped replication fork. Note: The DNA...

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DNA replication During the S phase of interphase, a second chromatid is assembled. The second  chromatid contains the exact same DNA found in the first chromatid. The copying  process, called  DNA replication,  involves separating (“unzipping”) the DNA molecule  into two strands, each of which serves as a template to assemble a new,  complementary strand. The result is two identical double-stranded molecules of DNA  that consist of a single strand of old DNA (the template strand) and a single strand of  new, replicated DNA (the complementary strand). Following are the steps involved in duplicating DNA. While studying the steps, refer to  Figure 4: 1. Each strand of DNA is labeled as 3#x2032 and 5#x2032. The 3#x2032  area terminates with a hydroxyl group and the 5#x2032 area terminates with  a phosphate group. 2. The enzyme helicase “unzips” (unwinds) the DNA helix, producing a Y-
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Unformatted text preview: shaped replication fork. Note: The DNA shown in Figure 4 is not depicted in a helical shape; it is drawn in a parallel form for ease of understanding. 3. RNA primers bring in respective base pairings to each of the original strands. DNA polymerase is an enzyme that binds the base pairings together, but it can only work in the direction of 5#x2032 to 3#x2032. 4. The other original strand also has to be put together 5#x2032 to 3#x2032 so it will be put together in a backward fashion. 5. In order to bind those base pairings to the original strand, a different enzyme called DNA ligase is necessary. This is called the lagging strand since it basically takes longer to put together. Figure 4. DNA Replication....
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DNA replication - shaped replication fork. Note: The DNA...

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