J.B. Gurdon's
cloning experiment
Took DNA from the African Clawed Frog (Xenopus laevis)
Destroyed the eggs from female using UV light for a few seconds. Killed the male albino frog
and took DNA from the intestine. Inserted the DNA into the fertilized egg after
removing the destroyed female DNA. The reproduction process continued as if
nothing happened. All offspring were albino males and had the same appearance.
Interpretations of the
experiment:
1.
Nucleus (DNA), not the cytoplasmic part of the
cell, regulates development
·
Because all of the cloned frogs resembled the
parent that donated the nucleus
2.
Specialized cells contain all the DNA that was
present in the original fertilized egg. Moreover, this DNA is not permanently
altered so that it becomes non-functional in specialized cells.
·
Because nucleus of specialized intestine cell
put into an egg caused it to develop into a complete organism
3.
The cytoplasmic environment restricts how the
nucleus DNA functions.
·
Because when the nuclei were put into eggs, they
coded for the development of an entire organism; whereas if left in the
intestine, they coded only for enzymes needed
