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Replication of DNA. Biology Standards 5 a and b. Phosphate. PO 4 Makes up a part of the DNA/RNA backbone. Sugar. In DNA, sugar is deoxyribose In RNA, sugar is ribose Binds to Nitrogen Base Is in backbone of DNA/RNA. DNA Base Pairing Rules. A only binds with T C only binds with G
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Replication of DNA Biology Standards 5 a and b
Phosphate • PO4 • Makes up a part of the DNA/RNA backbone
Sugar • In DNA, sugar is deoxyribose • In RNA, sugar is ribose • Binds to Nitrogen Base • Is in backbone of DNA/RNA
DNA Base Pairing Rules • A only binds with T • C only binds with G • H bonds hold Nitrogen bases together
DNAReplication • But, before a cell divides must duplicate its DNA. • Called DNA replication or DNA synthesis. • Each strand of DNA will serve as a template/model for a new strand of DNA.
DNA Replication 1st Step • Enzyme called DNA helicase unzips and unwinds a portion of DNA. • Enzyme helps breaks apart H that are connecting nitrogen bases. (A,T,C,G) DNA Helicase
DNA Replication: 2nd Step • 2nd enzyme called DNA polymerase comes along and begins to add complementary base pairs to nitrogen bases. • End result: 2 DNA molecules that are identical to each other.
RNA versus DNA Structure • 1st: RNA contains sugar ribose where as DNA has sugar deoxyribose. • 2nd: RNA is single stranded. DNA is double stranded. • 3rd: DNA has 4 nitrogen bases: AGCT. RNA has A, G, C, and Uracil instead of T.
Then, The Cell Divides… • Mitosis: Makes 2 identical diploid (2 copies of chromosomes) cells from 1 parent cell: IPMAT