DNA Replication
...ze discontinuous segments of polynucleotides (called Okazaki fragments). Another enzyme, DNA ligase then stitches these together into the lagging strand. There are four bases involved Adenine and Thymine are connected by two hydrogen bonds (non-covalent) while guanine and cytosine are connected by three. DNA Replication is semi-conservative When the replication process has been finished, two DNA molecules identical to each other and identical to the original have been produced. Each strand of the molecule has: • Remained intact as it served as the template for the synthesis of • a complementary strand Thus is mode of replication is called semi-conservative; one half of the new molecule is old, and the other half is halff-new. Types of RNA Messenger RNA (mRNA) - this will later be translated into a polypeptide. Ribosomal RNA (rRNA) - This will be used in the building of ribosomes: machinery for synthesizing proteins by translating mRNA. Transfer RNA (tRNA) – RNA molecules that carry amino acids to the growing polypeptides. Key Enzymes involved in DNA Replication Topoisomerase • Responsible for initiation for the unwinding of the DNA helix. • Lots of tension involved in holding the helix in its coiled and supercoiled nature, however just removing a single strand of DNA away can break this. Helicase • Accomplishes the unwinding of the original double strand, once supercoiling has been eliminated by the Topoisomerase. • Two strands want to bond together becaus...