Vector Biology and Gene Manipulation Questions and Answers Part-15

1. What are YEps?
a) Mutated yeast plasmids
b) Hybrid of yeast and bacteria
c) Yeast episomal plasmids
d) Transformed cells

Answer: c
Explanation: YEps are vectors derived from yeast plasmids. Some YEps contain the entire 2 micro-meter plasmids, others just include the origin of replication.

2. Yep13 is an example of _______
a) Yeast episomal plasmid
b) Host bacterium
c) Yeast integrative plasmid
d) Bacterial plasmid

Answer: a
Explanation: Yep13 is a yeast episomal plasmid derived from the 2 micro-meter plasmids. It includes only the original of replication from the parent plasmid.

3. What is a shuttle vector?
a) Hybrid vector
b) Mutated yeast plasmid
c) A vector that can be used with two/more systems
d) The transformed cell further used for transformation

Answer: c
Explanation: A shuttle vector is the one that can be used for transferring genetic material to more than one type of cells; essentially a eukaryotic and a prokaryotic system.

4. Yep13 is a shuttle vector.
a) true
b) false

Answer: a
Explanation: Yep13 includes the 2 micro-meter origin of replication, selectable LEU2 gene and the entire Pbr322 sequence. Hence it can be used for both yeast and E.coli.

5. For which of the following plasmids purification of a recombinant molecule from the transformed cell can be difficult?
a) Episomal plasmids
b) Integrative plasmids
c) Bacterial plasmid
d) All plasmids

Answer: b
Explanation: The yeast plasmid derived integrative plasmids are extremely difficult to purify from the host cell. These plasmids integrate into the host chromosome and remain their stable.

6. What does the word episomal in YEps indicate?
a) Expression
b) Replication
c) Independent replication
d) Mutation

Answer: c
Explanation: The word episomal in YEps indicates that it can replicate independently but also implies that integration into one of the yeast chromosomes can occur.

7. Why does the integration of YEp vector occur in a yeast chromosome?
a) Recombination
b) Smaller size
c) Similarity with host
d) Lytic cycle

Answer: a
Explanation: The integration of YEp vector into the host chromosome of yeast may occur because the host contains a mutated copy of the same gene

8. What is the role of homologous recombination in vector infection?
a) Integration
b) Host recognition
c) Duplication
d) Packaging

Answer: a
Explanation: Homologous recombination occurs between the YEp vectors and the yeast chromosome. This occurs because the homologous genes are present on both the plasmid and the host chromosome.

9. In homologous recombination what part of the plasmid gets integrated into the host?
a) Origin part
b) Cos sites
c) Entire plasmid
d) Gene of interest

Answer: c
Explanation: Homologous recombination can occur between plasmid gene and yeast mutant gene, resulting in the insertion of the entire plasmid.

10. What does “I” in Yips vectors stand for?
a) Infected
b) Integrative
c) Insertional
d) Initiation

Answer: b
Explanation: Yeast Integrative Plasmids, YIPs are basically bacterial plasmids carrying a yeast gene. An example is Yip5.