Tadpoles must undergo a major metamorphosis to become frogs. This change includes reabsorption of the tail, growth of limbs, calcification of the skeleton, increase in rhodopsin in the eye, development of lungs, change in hemoglobin structure, and reformation of the gut from the long gut of an herbivore to the short gut of a carnivore. Amazingly, all of these changes are induced by thyroxine. What is the most likely explanation for such a wide array of effects of thyroxine?

TLS Online TPP Program

#Question id: 39283

#Plant Biotechnology

Q. Statement I: In the fusion product described, the mitochondria are always derived from the donor strain (Parent B).

 Statement II: The chloroplasts in the resulting regenerants must always come from the recipient strain (Parent A)

TLS Online TPP Program

#Question id: 39284

#Plant Biotechnology

Q. Statement I: Fusing tomato protoplasts with irradiated Solanum acaule protoplasts produced plants that were morphologically identical to Solanum acaule. 

Statement II: The resulting tomato regenerants exhibited Cytoplasmic Male Sterility (CMS), which was inherited maternally.

TLS Online TPP Program

#Question id: 39285

#Plant Biotechnology

Q. Statement I: Protoplast fusion can be used to develop male sterile lines even between sexually incompatible species. 

Statement II: CMS lines developed through this method cannot be used with traditional CMS restorers.

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.