study2 - DNA is two nucleotide chains held together by...

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DNA is two nucleotide chains held together by bonds between A and T and between G and C. In replication, the two new chains separate, and their exposed bases are used as templates for the synthesis of two identical daughter DNA molecules. Genes encode the structure of proteins. To make protein, DNA is first transcribed by the enzyme RNA polymerase into a single-stranded working copy called mRNA. The nucleotide sequence in the mRNA is translated into an amino acid sequence that constitutes the primary structure of a protein. Amino acid chains are synthesized on ribosomes. Each amino acid is brought to the ribosome by tRNA. Replication is the process of copying a double-stranded DNA molecule to form two double-stranded molecules. Conservative replication would leave the two original template DNA strands together in a double helix and would produce a copy composed of two new strands containing all of the new DNA base pairs. 2 nd generation= 2 norm; 2 hybrid Dispersive replication would produce two copies of the DNA, both containing distinct regions of DNA composed of either both original strands or both new strands. 2 nd generation= 3 new; 1 original Semiconservative replication would produce two copies that each contained one of the original strands and one entirely new strand. 2 nd generation= 4 hybrid Replication fork -created by helicases , which break the hydrogen bonds holding the two DNA strands together. The resulting structure has two branching "prongs", each one made up of a single strand of DNA. The lagging strand is the DNA strand opposite the replication fork from the leading strand. It goes from a 3' to 5' . DNA is synthesized continuously on the leading strand and discontinuously on the lagging strand. Primase is a type of RNA polymerase that synthesizes a short stretch of RNA complementary to a specific region of the chromosome. On the lagging strand,
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This test prep was uploaded on 04/17/2008 for the course BIO 216 taught by Professor Mistry during the Spring '08 term at Dickinson.

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study2 - DNA is two nucleotide chains held together by...

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