This set of Gene Manipulation Multiple Choice Questions & Answers (MCQs) focuses on “Gene Manipulation in S.Cerevisiae”.
1. When was recombinant DNA technology first applied to fungi?
Explanation: When recombinant DNA technology was first applied to fungi in the late 1970s the organism of choice was the yeast Saccharomyces cerevisiae.
2. Yeast is a prokaryote.
Explanation: Yeast is a eukaryotic organism belonging to the kingdom of fungi.
It carries on processes such as mitosis, meiosis, signal transduction etc.
3. When was the complete sequencing of S. cerevisiae done?
Explanation: In 1996 the sequencing of the entire 12 Megabase genome of Saccharomyces cerevisiae was completed and most of the genes have been identified.
4. Fungi are not naturally _______________
Explanation: Fungi are not naturally transformable and special methods are required to introduce exogenous DNA to the fungal cells.
5. Spheroplasts are ____________ cells.
Explanation: One method of introducing exogenous DNA into fungi cells involves the use of Spheroplasts which are wall-less cells. These cells were first developed for S. cerevisiae.
6. How is the cell wall of cells removed?
c) By heating
Explanation: The cell wall is removed enzymatically and the resulting spheroplasts are fused with ethylene glycol in the presence of DNA and Calcium chloride.
7. Which of the following is an alternate method for spheroplasts?
Explanation: Electroporation provides a simpler and more convenient alternative to the use of spheroplasts. Cells transformed by electroporation are selected on solid media.
8. Spheroplasts are added to a medium containing _____ percent of agar.
Explanation: The spheroplasts are then allowed to generate new cell walls in a stabilizing medium containing three percent agar. This makes retrieval of cells convenient.
9. Which of the following is an enterobacterial plasmid?
Explanation: DNA can also be introduced into yeasts and filamentous fungi by conjugation. Few scientists found that entero-bacterial plasmids, such as R751.
10. R751 is an IncP-beta plasmid.
Explanation: Enterobacterial plasmids such as R751 and F can facilitate plasmid transfer by E.coli to S.cerevisiae and Schizosaccharomyces pombe.
11. Exogenous DNA that is not carried on a vector can only be maintained by _____________ into a chromosome.
Explanation: In the original experiments on the transformation of S. cerevisiae, Hinnen transformed leucine auxotroph with the plasmid pYeLeu 10.
12. What are dominant selectable markers?
a) Drug-resistance genes
b) Inducing genes
c) Exogenous genes
d) Endogenous genes
Explanation: The dominant selectable markers are usually drug-resistance genes of bacterial origin and transformed cells are selected on a medium that contains the drug at an appropriate concentration.
13. Methotrexate is an analog of __________
c) Folic acid
Explanation: Methotrexate is a folic acid analog, which is a competitive inhibitor of the enzyme dihydrofolate reductase (DHFR).
14. With respect to mammalian cell cloning, salmon sperm DNA can serve as a source of ____________
a) Non-specific carrier
b) Specific carrier
c) Genomic DNA
d) Plasmid DNA
Explanation: Calcium phosphate transfection is mostly used and the specific donor DNA is often bulked with a non-specific carrier such as cleaved Salmon sperm.
15. One application in which the use of plasmid vectors is critical, in the case of mammals is ____________
a) Stable transformation
b) Transient transformation
Explanation: One application in which the use of plasmid vectors is critical, in the case of mammals is transient transformation. Here the goal is to exploit the short-term persistence of extrachromosomal DNA.
Sanfoundry Global Education & Learning Series – Vector Biology & Gene Manipulation.
To practice all areas of Vector Biology & Gene Manipulation, here is complete set of 1000+ Multiple Choice Questions and Answers.