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1. Forklare at DNA replikation foregår semikonservativ, og at princippet i DNA replikation er den samme i prokaryote og eukaryote organismer. Replikation foregår samtidig på begge strenge og er derfor bidirektionel.
Stryer, s.123
Devlin, s.162-3

The double-helical model of DNA and the presence of specific bas pairs immediately suggested how the genetical material might replicate.

The sequence of bases on one strand of the double helix precisely determines the sequence of the other strand. Thus, separation of the double helix into two component chains would provide two single stranded templates, onto which two double helices could be constructed. 

This is called semi conservative replication, because the new DNA helix will contain one parent strand and a newly synthesized complementary strand (a copy of the complementary parental strand).

The basic principle of replication can be seen both in prokaryotes and eukaryotes. There are, of course, some differences. Fx. there are different enzymes involved in the process.

The replication begins at specific DNA sequences called organs of replication, and proceeds bidirectionally and at the same times on both strands. One strand is made continuously while the other is synthesized in fragments.

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