Read the following four statements (A-D) with certain mistakes in two of them. Which are the two statements having mistakes?
- Statements (B) and (C)
- Statements (A) and (C)
- Statements (A) and (B)
- Statements (C) and (D)
Answer
(3) Statements (A) and (B)
Solution
(A) Mistake: as per NCERT, in 1997 the first transgenic cow (not buffalo), Rosie, produced human protein-enriched milk containing human alpha-lactalbumin.
(B) Mistake: restriction enzymes cut DNA at specific sites; isolation of DNA from other macromolecules is done by lysozyme/cellulase/chitinase, RNase, protease and precipitation with chilled ethanol.
(C) Correct: downstream processing (separation and purification of the product) is a step of rDNA technology.
(D) Correct: disarmed pathogens such as Agrobacterium (Ti plasmid) and retroviruses are used as vectors.
∴ Statements (A) and (B) have mistakes.
Answer: (3)