Download Central Dogma Review Sheet

Central Dogma Review Sheet
Honors Biology
*Review the structure of proteins. You should know the relationship of amino acid to proteins, and
know what a peptide bond is. Review also enzymes, particularly the importance of enzyme shape
(particularly the active site) to its function.
1. Be able to describe the structure of DNA, including the numbering of the carbons in the
deoxyribose sugar. Know the four bases of DNA, and be able to characterize each as purine or
pyrimidine.
2. Likewise, be able to describe the structure of RNA. Be able to list differences between DNA and
RNA, and recognize the two by sight.
3. Understand how base pairing works. Know that A hydrogen-bonds with T, and C bonds with G.
Be able to give the reasons why the base pairing is so specific.
DNA Replication
4. Be able to explain why DNA is replicated, and when this occurs in the cell cycle. Why is the
fidelity of replication (how accurately it is copied) important?
5. Be able to describe the roles of the following enzymes in DNA replication: Helicase, SSB,
Primase, DNA Polymerase, and DNA ligase.
6. Understand why the two strands of the DNA molecule are replicated differently. Be able to
identify the leading and lagging strands. Be able to explain what Okazaki fragments are.
Transcription
7. Be able to explain why DNA is temporarily copied into mRNA, and not used directly.
8. Know the role of RNA polymerase in transcription. Be able to define the promoter and
terminator regions.
9. Be able to list and explain the modifications to mRNA, including the mG 5’ cap, the polyA tail,
and splicing by the spliceosome. You should also be able to describe introns and exons.
Translation
10. Be able to explain the roles of the four types of RNA molecules: mRNA, tRNA, rRNA, and
ribozymes.
11. Be able to describe briefly the process of translating an mRNA into a protein. You should:
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Be able to recognize start codons and stop codons by sight.
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Using a Genetic Code Table, translate the codons into the amino acids
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You should be able to briefly describe how one of the different tRNAs recognizes specific
codon (via the anticodon). You should then be able to describe how the ribosome
synthesizes the protein, including the role of the E, P, and A sites. Be able to explain
how the stop codon is read. Know that about 3 ATP equivalents are needed to form one
peptide bond.
Mutations
12. Be able to define mutation, and recognize and determine the effects of the following the
mutations on a DNA coding sequence:
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Point mutations (especially silent mutations)
Nonsense mutations
Run-on mutations
Frameshift mutations
Remember that mutations are not always bad: they can be neutral or even beneficial.
13. Be able to discuss causes of mutations.