Investigators performed nuclear transplant experiments to determine whether DNA is altered irreversibly during development. Which of the following statements about these experiments is true?
(a) Because the donor nucleus is taken from an adult animal, the chromosomes from the nucleus must undergo recombination with the DNA in the egg for successful development to occur.
(b) The embryo that develops from the nuclear transplant experiment is genetically identical to the donor of the nucleus.
(c) The meiotic spindle of the egg must interact with the chromosomes of the injected nuclei for successful nuclear transplantation to occur.
(d) Although nuclear transplantation has been successful in producing embryos in some mammals with the use of foster mothers, evidence of DNA alterations during differentiation has not been obtained for plants.
Choice (b) is correct. The meiotic spindle and the nucleus in the egg are usually removed in these experiments [choices (a) and (c)]. Some differentiated plant cells have the ability to de-differentiate and regenerate an entire adult plant, providing evidence that DNA is not irreversibly altered during development [choice (d)].
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Why is the idea of “special creation” not a viable alternative to the theory of evolution?
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Why must the transfer of electrons from glucose to oxygen during aerobic respiration take place in a series of steps?
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In the Beadle and Tatum study, it was important that Neurospora was haploid because:a
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