Genetic Research and Biotechnology Test

1.  The discovery of restriction endonucleases was crucial to the development of recombinant DNA technology because these enzymes

2. When recombinant DNA is formed, it is necessary to join the sugar-phosphate backbones of the plasmid DNA and the introduced DNA. Which of the following is used to do this?

3. Dideoxynucleosides are employed in the course of the Sanger process of DNA sequencing. Dideoxynucleosides are used because

4. Gel electrophoresis separates fragments of DNA using

5.  A fragment of DNA is called recombinant if

6. Which of the following tools of recombinant DNA technology is incorrectly paired with its use?

7. Restriction endonucleases (restriction enzymes) can break

8. The restriction endonuclease AluI leaves blunt ends on DNA fragments after digestion. These blunt ends

9.  What is the name of the process that introduces DNA into bacterial cells?

10.  During the polymerase chain reaction, heat is used to

11. Taq polymerase was isolated from

12. Plant cells are hard to transform because they have

13.  Plants are more readily manipulated by genetic engineering than are animals because

14. In recombinant DNA methods, the term vector can refer to

15. When using the shotgun approach to genome mapping, researchers carry out

16. Stem cells such as adult stem cells are said to be pluripotent, meaning they can give rise to

17.  Which of the following biotechnology products is a result of gene pharming?

18.  In the cloning of Dolly the sheep, what was the source of the genetic material?

19.  What are the dideoxynucleotides used in dideoxy sequencing of DNA?

20.  What type of vector is specifically used to produce desirable genes into host plant cells resulting in the production of transgenic plants?

21.  The following are all steps in the production of a bacterium having recombinant DNA, which includes an inserted nonbacterial gene. They are in random order.

1. gel electrophoresis of plasmid DNA from bacteria in colonies showing antibiotic resistance
2. sticky ends are allowed to pair up
3. a restriction endonuclease is used to remove the gene to be inserted from its source and also to cut open a plasmid that includes a gene for antibiotic resistance
4. the bacterial colonies are treated with antibiotic
5. treatment with ligase
6. transformation

The correct order of these steps is

22.  The recognition sites of five restriction endonucleases are shown below. Which would make cuts in the following DNA fragment? You will need to draw in the complementary DNA strand before attempting this question.

5′-GCAAGCTTGCTGCAGAATTACCCGGA-3′

Recognition Sites

23.  By mistake, DNA fragments were loaded onto a gel using a buffer with a pH so low that all the phosphate groups of the DNA nucleotides were protonated (i.e., had H⁺ ions added to them.) Subsequent electrophoresis failed to separate the fragments. This was because

24. Restriction endonuclease digestion of a DNA sequence yielded fragments of the following sizes:

25.  A paleontologist has recovered a bit of tissue from a 400-year old present skin of an extinct dodo (bird).  The research intends to compare the DNA from the sample with that of living birds.  Which of the following would be most useful for increasing the amount of dodo DNA available for testing?

26.  The view has been expressed that there is really no difference between producing new plant and animal varieties by genetic engineering and producing new varieties by traditional selective breeding methods and hybridization. Do you agree? Explain.

27.  There is a possibility that gene flow due to cross-pollination may occur between crop plants genetically modified to be herbicide resistant and neighbouring wild plants. Why would this be a problem?

28.  What would you consider the most important question to ask when evaluating the pros and cons of a new GMO for use in gene pharming?

29.  Rice is a staple food for millions of people worldwide.  Unfortunately, current rice varieties lack vitamin A.  Short supply of vitamin A in the diet is the leading cause of blindness in small children.   Scientist have developed a new form of rice, golden rice with enriched levels of vitamin A.

a.  Given its nutritional value, should golden rice be planted worldwide?

b.  What information would you need to make your decision?

30.  You wish to excise a gene from a human chromosome and to incorporate it into a plasmid vector. Explain why it is important to use the same restriction endonuclease (restriction enzyme) to remove the gene from the chromosome and to open up the plasmid ring.