BIO Final Review PDF

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Final review of BIO...

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DNA has to grow in the 5’ → 3’ direction - DNA polymerase acts on the 3’-OH to add nucleotides. All depends on DNA Polymerase’s ability to bind. Why do the two strands have to be antiparallel? - Parallel → it is important to be antiparallel so DNA replication can occur. There are base pairing rules because if A bonded with G or C with T, the DNA would lose its shape and problems would arise. - A — (2 bonds) — T, C — (3 bonds) — G What are the steps needed to replicate DNA? - Replication fork — unzipped (helicase) - RNA primer binds to 3’ end of the strand to start replicating — primers are created by RNA primase. - Elongation — DNA polymerase creates new strands, while other polymerases check for errors. Replaces RNA primers. - Okazaki fragments = primers - Telomerase — catalyzes the synthesis of telomere sequences. Why are enzymes needed anyway? - Because they need to assist in carrying out cellular functions — each enzyme has a specific function. Also, enzymes lower needed energy, helping start reactions that may not have been able to happen otherwise. Why “lagging” - Because enzyme can only read in one direction What makes phosphodiester - DNA Ligase Why bother removing the RNA primer? - This RNA is chemically unstable and the presence of wrong sugar — What are some important differences between PCR and DNA replication in cells?

PCR -

One specific gene sequence Taq Polymerase (heat-loving) Replications of all the same length Heated to denature strand

DNA Replication Not especially replicating a certain sequence Replicated strands of all different lengths DNA Polymerase Pulled apart with DNA helicase

What are some parts of a eukaryotic gene and their function?

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Proteins called transcription factors can bind to the TATA box and recruit an enzyme called RNA polymerase, which synthesizes RNA from DNA.

What are the steps of the processing of the mRNA molecule?

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What is the genetic code? What might happen if a point mutation (1 base change) occurred within a codon? - Genetic code = the nucleotide triplets of DNA and RNA molecules that carry genetic information in living cells. - If one base change occurs, everything can change — protein can become different/unusable and things can go wrong...