Homozygous: this means that the man has two genes for unattached earlobes, so whichever of these gene genes is transmitted to the child, it will be unattached. Since having unattached earlobes is a result of a dominant gene, one such gene is enough and the child will definitely have an unattached earlobe.
The answer to this is older, but it's not a proven fact even though schools teach it as if it were. It is still just a theory if you think about it with how much the earth moves, areas of rock could be complete upside down and no one would know, it would be like history in reverse.
In everyday life, a "theory" means a hunch, or a figure. In science a theory is the demonstrated consequence of a few trials. i.e. nuclear theory... we realize that molecules exist and that everything is made of iotas, yet in science the expression "law" is not utilized as a part of the case that ensuing confirmation ever surfaced to make a superior or more exact theory.
