Agrobacterium tumifaciens, is able to deliver a piece of DNA known as _____________ to transform normal plant cell into a tumor cell.
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → T-DNA
Option (1) T-DNA — Correct. T-DNA (transferred DNA) is part of the Ti plasmid of Agrobacterium tumifaciens. Because it can move into plant cells, the Ti plasmid has been changed into a cloning vector that carries useful genes into plants without causing disease.
Option (2) Z-DNA — Incorrect. Z-DNA is a left-handed form of the DNA double helix, not a piece of DNA that a bacterium sends into a plant.
Option (3) B-DNA — Incorrect. B-DNA is the usual right-handed double helix described by Watson and Crick.
Option (4) C-DNA — Incorrect. C-DNA is another rare form of the DNA helix. It should not be confused with cDNA (complementary DNA), which is made from mRNA.
NCERT Extract:
Cloning Vectors – …
