Answer:
homo sapiens ,living organism's
If you wanted to obtain 100% roan calves, then it si required to cross parents who are homo-zygous (pure lines) for the genes associated with this trait.
<h3>What is a homo-zygous individual?</h3>
A homo-zygous is an individual who has the same gene variants or alleles for a given gene locus.
Conversely, a heterozygous is an individual who has different gene variants or alleles for a given gene locus.
In breeding, pure lines (or purebred) are homo-zygous individuals that may be crossed to obtain the desired trait in the descendence.
Learn more about homo-zygous individuals here:
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The blank spaces in the task content should be filled with is; Three(3), atmosphere and ultraviolet rays of the sun.
<h3>What is Ozone?</h3>
Ozone is a trioxygen molecule; contained in the upper atmosphere with a sole aim of protecting biological life against ultraviolet rays of the sun. The ozone layer is however depleted to Oxygen molecule in the lower atmosphere.
Read more on ozone layer;
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