Explanation:
However, in 2016 researchers published a new set of Neanderthal DNA sequences from Altai Cave in Siberia, as well as from Spain and Croatia, that show evidence of human-Neanderthal interbreeding as far back as 100,000 years ago farther back than many previous estimates of humans' migration out of Africa (Kuhlwilm Dec 11, 2020
<h2><u>Answer</u> :</h2>
The correct option is A. If a dominant allele is present, the recessive allele won’t be seen.
The dominant allele is the one which appear, and the recessive one isn't shown.
For example - If a person has 2 alleles of eye colour as B ( black ) and b ( brown ), in which black is dominant and the brown one is recessive, then the person will have black eye colour because only dominant allele shows its characteristics.
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The f1 generation may have genes for short plants just that the genes for long plants are dominant over the genes for short plants(recessive) so when cross pollination happen and that two f1 long plants which are homozygous cross pollinate, the recessive genes have a chance of being paired up in new offspring(F2 offspring) thus the possiblity of short plants in f2 generation
What attraction does the positive ab have with the negative ab?