| What is DNA combined from two different organisms called? | Recombinant DNA |
| What is meant by "Universal DNA?" | Every living organism uses the same genetic code with the system involving DNA to RNA to Protein. |
| What enzyme used by retroviruses such as the coronavirus Sars-COV-2 enables RNA to be converted to single-stranded cDNA? | Reverse Transcriptase |
| What enzymes produced naturally as a protection mechanism by bacteria can be used to cut DNA into fragments? | Restriction endonucleases enzymes, or just restriction enzymes. |
| What is a restriction site? | A specific base sequence targeted by a specific restriction enzyme due its complementary active site |
| The restriction enzyme HindIII "recognises" the DNA restriction site AAGCTT and cuts to produce overhanging bases. These are are called? | "Sticky ends" |
| What enzyme synthesises messenger RNA - mRNA - from a DNA sense strand? | RNA polymerase |
| What are the names for the DNA regions where transcription of mRNA starts and finishes? | Promotor region and terminator region |
| What are plasmids and what is their role in genetic engineering? | Small circular lengths of DNA that contain antibiotic resistance genes. They are used as vectors for a transport recombinant DNA "gene" into another organism. |
| Genes used in plasmids to identify gene take-up include antibiotic-resistance genes, lactase synthesising genes, as well as GFP, or Green fluorescent Protein genes are examples of what type of gene? | Marker Genes |
| What is PCR? | Polymerase Chain Reaction |
| What does PCR do and why is this described as "In vitro" gene cloning. | PCR is used to amplify small quantities of DNA. It takes place "In vitro" which literally means "In glass" or more precisely outside the living body (In vivo) |
| What is the role of the enzyme DNA polymerase in PCR? | Joins DNA nucleotides in correct sequence according to single DNA template strand. |
| In PCR, how are double DNA strands separated? | By heating to 95 degrees C - this is know as "melting" |
| Why is taq polymerase used? | It is thermostable (heat tolerant) at the higher than normal body temperatures used in the melting stage. |
| In PCR, what is the short, single-stranded DNA that provides the starting sequences for DNA polymerase to begin DNA copying called? | Primers |
| What is the name for the process that allows primers to bind to a complementary DNA base sequence? and what must happen to the temperature for this to happen? | Annealing, that happens when the high melting temperature is lowered - 55 degrees C. |
| What does the technique of DNA fragment analysis by Gel electrophoresis achieve? | Separates DNA fragments according to their molecular size |
| In genetic fingerprinting, what are VNTR's and STR's? | Variable Number Tandem Repeats and Short Tandem Repeats. These repetitive non-coding sequences can be digested with restriction enzymes to provide different-sized fragments that can identify individuals. |
| How does Gel electrophoresis separate the different-sized fragments that are digested by the restriction enzymes? | Resisted by the gel, negatively-charged DNA fragments are pulled towards the positive end of electrophoresis tank. The smaller fragments travel at a faster rate and form bands in "bar-code" pattern that determines the size of the fragments. |
| What role does DNA hybridisation play in the genetic fingerprinting process? | Single-stranded DNA, radioactive or fluorescent probes bind to complementary sequences on VNTR's/STR's to enable visualisation. |
| What is meant by "55 Kbp" with reference to digested DNA strands | The strands are 55 thousand base pairs long, with base pairs forming a constant length measurement to provide the unit of DNA fragment measurement. |
