Biology Review Book (BRB) prompts:

2.7 DNA replication, transcription & translation

2.7.1 Meselson and Stahl obtained evidence for semi-conservative replication of DNA. Describe their test and findings. (including the rejection of conservative replication and dispersive replication) (2)

2.7.2 Explain the significance of complementary base pairing in the conservation of the base sequence of DNA. (3)

2.7.3 State the functions of the enzymes needed for DNA replication to make new strands of DNA (helicase, RNA primase, DNA polymerase III (adds nucleotides), DNA polymerase I (removes RNA primer and adds DNA), ligase) (1)

2.7.4 DNA has two strands. In DNA replication, one is called the leading and the other is the lagging strand. State how each strand can be identified. (1)

2.7.5 DNA has two strands. In making a polypeptide (protein synthesis), one is called the sense strand and the other is the antisense strand. State how each strand can be identified. (1)

2.7.6 Distinguish transcription from DNA replication, in terms of enzymes used and product. (2)

2.7.7 Outline the process of translation in the cytoplasm, leading to polypeptide formation – using the terms codon, ribosome, polypeptide, amino acid, tRNA and mRNA. (2)

2.7.8 Describe the genetic code in terms of codons composed of triplets of bases and why there are 64 possible codons. (2)

2.7.9 Discuss how the production of human insulin in bacteria can be used as an example of the universality of the genetic code. (3) *

2.7.10 PCR – polymerase chain reaction. State the function of PCR. (1) *

2.7.11 Taq DNA polymerase is an enzyme taken from a thermophilic bacteria called Thermus aquaticus. Describe the process and rate of replication of DNA using PCR. (2) *

2.7.12 Using a genetic code table (aka codon table), deduce the amino acids in the sequence on the wall if it is the sense strand. (2)

*Leave a gap for these – we will be addressing these in 3.5 (After spring break)