Questions and Answers

Outline the benefits of using databases that provide information about nucleotide sequences of genes and genomes, and amino acid sequences of proteins and protein structures

Outline how microarrays are used in the analysis of genomes and in detecting mRNA in studies of gene expression

Describe and explain how gel electrophoresis is used to separate DNA fragments of different lengths

Describe and explain the steps involved in the polymerase chain reaction (PCR) to clone and amplify DNA, including the role of Taq polymerase

Explain that gene editing is a form of genetic engineering involving the insertion, deletion or replacement of DNA at specific sites in the genome

Explain how gene expression may be confirmed by the use of marker genes coding for fluorescent products

Explain why a promoter may have to be transferred into an organism as well as the desired gene

Explain the roles of restriction endonucleases, DNA ligase, plasmids, DNA polymerase and reverse transcriptase in the transfer of a gene into an organism

Explain that genes to be transferred into an organism may be: • extracted from the DNA of a donor organism • synthesised from the mRNA of a donor organism • synthesised chemically from nucleotides

Explain that genetic engineering is the deliberate manipulation of genetic material to modify specific characteristics of an organism and that this may involve transferring a gene into an organism so that the gene is expressed