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2.1 Transgenics & Recombinant Systems — Test 1
Q1. A transgenic organism is one that:✓ Carries a stably integrated foreign gene (transgene)
Q2. The classic method for producing transgenic mice introduces DNA by:✓ Microinjection into the pronucleus of a fertilised egg
Q3. Electroporation introduces DNA into cells by:✓ Applying a brief electric pulse that makes the membrane permeable
Q4. Lipofection delivers DNA into cells using:✓ Lipid vesicles (liposomes) that fuse with the cell membrane
Q5. The biolistic (gene-gun) method introduces DNA by:✓ Firing DNA-coated micro-particles into cells
Q6. A common reason for using a viral (e.g. retroviral) vector to make transgenics is that it:✓ Efficiently delivers and integrates genes into the host genome
Q7. A reporter gene such as GFP (green fluorescent protein) is included in a construct to:✓ Visibly indicate whether and where the construct is expressed
Q8. Bt crops express an insecticidal protein derived from the bacterium:✓ Bacillus thuringiensis
Q9. A genetically modified organism (GMO) is best defined as an organism whose genetic material has been:✓ Altered using genetic-engineering techniques
Q10. After making a transgenic animal, the presence of the integrated transgene is typically confirmed by:✓ PCR or Southern blotting of genomic DNA
Q11. Expression of a transgene at the protein level is best confirmed by:✓ Western blotting (or immunoassay)
Q12. A tissue-specific promoter is included in a transgenic construct so that the transgene is:✓ Expressed only in particular tissues
Q13. In pronuclear microinjection, the transgene usually integrates into the genome:✓ Randomly, at one or a few sites
Q14. A selectable marker such as the neomycin-resistance (neo) gene is used in animal-cell transformation to:✓ Select cells that have taken up the construct (e.g. on G418)
Q15. Embryonic stem (ES) cells are valuable for making genetically modified animals because they are:✓ Pluripotent and can contribute to all tissues of the resulting animal
Q16. Agrobacterium tumefaciens transfers genes into plant cells using a segment of its Ti plasmid called the:✓ T-DNA
Q17. A 'knock-in' transgenic, unlike a randomly integrated transgenic, has the new gene placed:✓ At a specific, predetermined location in the genome
Q18. Recombinant proteins of pharmaceutical value (e.g. produced in the milk of transgenic animals) are an example of:✓ Molecular farming (pharming)
Q19. Compared with chemical transfection, viral vectors generally offer:✓ Higher gene-transfer efficiency, especially in hard-to-transfect cells
Q20. Match each gene-transfer method with its description and select the correct option.✓ A-iii, B-i, C-iv, D-ii