Tumor-suppressor genes encode proteins with which of the following functions?

a. growth-promoting               b. growth-arresting                  c. pro-apoptotic

d. anti-apoptotic                      e. DNA repair

TLS Online TPP Program

#Question id: 39286

#Plant Biotechnology

Q. Assertion: Cybrids can be produced by the irradiation of protoplasts from one of the fusion parents. 

Reason: Irradiation effectively inactivates the nucleus of the donor protoplast, allowing only its cytoplasm to contribute to the fusion product.

TLS Online TPP Program

#Question id: 39287

#Plant Biotechnology

Q. Assertion: Cybridization is a valuable tool for transferring traits like cytoplasmic male sterility (CMS) and herbicide resistance in crops like rice and tobacco. 

Reason: Cybrids contain the nuclear genome of only one species, which ensures the plant retains its primary species characteristics while gaining specific cytoplasmic traits.

TLS Online TPP Program

#Question id: 39288

#Plant Biotechnology

Q. Assertion: Cybrids allow for the combination of mitochondria from one species with chloroplasts from a different species.

 Reason: This combination can be used to overcome deleterious effects, such as chlorophyll deficiency, found in some alloplasmic lines.

TLS Online TPP Program

#Question id: 39289

#Plant Biotechnology

Q. Assertion:Brassica napus lines carrying Ogura (radish) cytoplasm are highly efficient for commercial growth in cold climates without any modifications. 

Reason: The presence of radish chloroplasts in these lines causes chlorophyll deficiency under low temperatures.

TLS Online TPP Program

#Question id: 39290

#Plant Biotechnology

Q. Assertion: Protoplast fusion between CMS B. napus (with radish cytoplasm) and normal B. napus can produce healthy male sterile plants. 

Reason: The resulting cybrids can retain the radish mitochondria (for CMS) while replacing the radish chloroplasts with B. napus chloroplasts.

TLS Online TPP Program

#Question id: 39291

#Plant Biotechnology

Q. Assertion: In plant breeding, cytoplasm transfer via somatic hybridization is significantly faster than conventional backcrossing. 

Reason: Protoplast fusion can achieve in one year what typically takes 5–6 years through the backcrossing method.