Gene Manipulation test focuses on “Gene Manipulation in Fruitflies”.
1. Gene transfer to fruit flies involves microinjection of DNA into the nucleus.
A. True
B. False
Answer: B
Clarification: Gene transfer to fruit flies involves the microinjection of DNA into the pole plasma. P elements are used to introduce exogenous DNA.
2. P elements introduce DNA into the Drosophila _________
A. Somatic cells
B. Cytosol
A. Germline
D. Totipotent cells
Answer: C
Clarification: P elements, also known as transposons and jumping genes are used to introduce DNA into the Drosophila germline. These are transposable DNA elements.
3. P elements are highly __________
A. Toxic
B. Mobile
A. Erroneous
D. Acidic
Answer: B
Clarification: P elements are transposable DNA elements that under certain circumstances can be highly mobile in the germline of D. melanogaster.
4. The P-M hybrid dysgenesis is a _________
A. Technique
B. Syndrome
A. Apparatus
D. Strain
Answer: B
Clarification: P elements cause a syndrome of related genetic phenomena called P-M hybrid dysgenesis. It occurs when males of a P strain are mated with females of an M strain.
5. The P-M hybrid dysgenesis syndrome results in abnormal _____________
A. Offspring
B. Strain
A. Gene
D. Protein
Answer: A
Clarification: The syndrome predominantly affects the germline and induces a high rate of mutation and frequent chromosomal aberrations, resulting in an abnormal offspring.
6. Eggs permissive for P-element transposition are called __________
A. P-cytotype
B. M-cytotype
A. L-cytotype
D. K-cytotype
Answer: A
Clarification: P-elements are mobilized in the eggs of M-strain females. Eggs that are permissive for P-element transposition are described as M-cytotype.
7. P-element encodes a repressor of its own.
A. True
B. False
Answer: A
Clarification: The P-elements cause dysgenesis in crosses within P strains, because they are not mobilized in P-cytotype eggs. P-element encodes a repressor for itself which prevents transposition.
8. The P-elements have ______ base pairs inverted terminal repeats.
A. 11
B. 21
A. 31
D. 41
Answer: D
Clarification: The elements are characterized by perfect 31 base pairs inverted terminal repeats which are recognized by the transposase.
9. A truncated version of which enzyme can act as repressor?
A. Transposase
B. Polymerase
A. Nuclease
D. Ligase
Answer: A
Clarification: The prototype element contains a single gene, comprising four exons, encoding the transposase; a truncated version of transposase may act as a repressor.
10. Primary transcript of which enzyme is differentially spliced in germ cells and somatic cells?
A. Polymerase
B. Helicase
A. Ligase
D. Transposase
Answer: D
Clarification: The transposase primary transcript is differentially spliced in germ cells and somatic cells, such that functional transposase is produced only in germ cells.
To practice all areas of Gene Manipulation for tests, .