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:
brainly.com/question/13760394
Answer:
Habitat Isolation
Explanation:
Ecological, or habitat, isolation occurs when two species that could interbreed do not because the species live in different areas.
<span>My pea plant has an unknown genotype for flowers, whether it has two dominant traits for white flowers (WW) or one dominant and one recessive (Ww) leading to white flowers; therefore I am doing a testcross in order to determine the genotype of my pea plant. The best plant to do this with is one that has a phenotype of purple flowers (ww) - that is, it is homozygous for the recessive trait.
If I use a homozygous recessive plant, I know exactly what its genotype is. I don't have to worry about whether it's got one or two dominant alleles; I know that at least half of my alleles are going to be the recessive w.
This makes identifying the offspring's genotype very simple. If I find that the offspring have at least some purple flowers among them, I know that my original plant had to be Ww; that is it had to have one dominant and one recessive allele for the flower color gene. If, however, all of the offspring are white flowers, I know that my original pea plant had both dominant alleles (WW).</span>
Airborne nitrogen is one of the largest sources of pollution affecting the Chesapeake Bay and its tributaries. Excess nitrogen can fuel the growth of algae blooms, which can block sunlight from reaching underwater grasses and create low-oxygen “dead zones” that suffocate marine life.
