The histone tails are required for chromatin to condense from the beads-on- a-string conformation into the 30-nm fiber. Recent experiments indicate that the N-terminal tails of histone H4, particularly_____________, are critical for forming the 30-nm fiber.

TLS Online TPP Program

#Question id: 39262

#Plant Biotechnology

Q. Assertion: The fusion of B. napus (AACC) and B. nigra (BB) results in a hybrid with the genomic constitution AABBCC. 

Reason: This specific interspecific fusion was primarily conducted to transfer resistance against Phoma lingam (black-leg disease) to rapeseed.

 

TLS Online TPP Program

#Question id: 39263

#Plant Biotechnology

Q. Assertion: Somatic hybridization between non-flowering and male sterile dihaploid clones of potato can result in male fertile hybrids. 

Reason: Symmetric hybridization allows for the creation of superior hybrids and the generation of novel genetic material by bypassing traditional sexual reproduction barriers.

TLS Online TPP Program

#Question id: 39264

#Plant Biotechnology

Q. Assertion: Tobacco hybrids produced from N. rustica and N. tabacum may exhibit resistance to blue mould. 

Reason: Blue mould resistance was a primary trait present in both parent lines and was intentionally selected for during the initial fusion process.

TLS Online TPP Program

#Question id: 39265

#Plant Biotechnology

Q. Assertion: Symmetric hybrids are utilized to widen the genetic base of allopolyploid species.

 Reason: Producing synthetic lines of Brassica napus by fusing B. oleracea and B. campestris introduces desirable traits that might be missing in the current cultivated pool.

TLS Online TPP Program

#Question id: 39266

#Plant Biotechnology

Q. Assertion: Somatic hybrids of potato fused with S. brevidens are used in breeding programs to combat Potato Leaf Roll Virus (PLRV). 

Reason:S. brevidens is a wild relative of the potato that carries natural resistance to certain viral and bacterial diseases like Erwinia soft rot.

TLS Online TPP Program

#Question id: 39267

#Plant Biotechnology

Q. Superior somatic hybrids showing 20–25% higher alkaloid content and potential for industrial scopolamine production were obtained from fusion between: