Answer:
Stem cells are currently being used to replace damaged cells or to treat some forms of cancer, usually taken from the adult hip (bone marrow)
I believe that present day was a theory that became a evolution developed because it was a historical event involved
Answer is: <span>A. During crossing over, genetic information is exchanged between two homologous chromosomes.
</span>Crossing over results in recombinant chromosomes<span> during </span>sexual reproduction, <span>increases the genetic diversity of sexually reproducing organisms.
</span><span>In crossing over matching regions on matching chromosomes break and then reconnect to the other chromosome.</span>
Artificial selection is the type of selective breeding.
Selective breeding is process of breeding parents with distinct characteristics to produce offspring with more desirable characteristics.
Most of the time the breed of dogs were formerly selected for particular purposes, such as hunting or guarding which needs strong physical endurance. Hence, Selective breeding is evolved by human selection. For example racehorses, having particular traits are desirable in different breeds of dogs that compete in dog shows. Artificial selection, is selective breeding that is imposed by an selective process, in order to get the phenotype of desirable features.
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