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The principal enzyme involved in DNA replication is called _____________. The enzyme joins ________________ to synthesize a new _______________ strand of DNA. DNA replication is called ______________ because each new DNA molecule is made up of one original and one new strand.


complementary

DNA polymerase

nucleotides

semiconservative

User Yakov Manshin
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Answer:

The principal enzyme involved in DNA replication is called _DNA polymerase_. The enzyme joins _nucleotides_ to synthesize a new __complementary_ strand of DNA. DNA replication is called __semiconservative__ because each new DNA molecule is made up of one original and one new strand.

Step-by-step explanation:

DNA replication is the process through which DNI molecule duplicates. This event takes place during the S stage of the interphase. So when the cell divides during mitosis or meiosis, each cell will get a complete set of chromosomes.

DNI replication is semi-conservative because each new molecule carries an original DNI strand and a new one. The fact that the new molecule is composed of an original strand makes it semi-conservative. The old existing strands are used to synthesize the new complementary strand.

The origin of the replication requires helicase enzymes to break hydrogen bonds and separate the two original strands. The topoisomerase enzyme is necessary to release tension. Other proteins are also needed to join the strains and keep them separated. Once the molecule is opened, there is a region named replication forks. DNA polymerase makes the new nucleotides enter into the fork and pairs them with the corresponding nucleotide of the original strand. Adenine pairs timine, and cytosine pairs guanine.

DNA strands are antiparallel, and replication occurs only in 5´-3´direction. So one of the strands will replicate continuously, while the other strain will be formed by short fragments known as Okazaki fragments.

Primers are needed to make the DNA polymerase work. Primers are small units of RNA and are placed at the beginning of each new fragment.

User PatlaDJ
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