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Question of science.
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We are dealing with three generations of genetics, so parental generation f1 and f2.
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So we're starting with the parental generation where we're told one parent has the genotype of being homozygous dominant at both genes, which homozygous homo means same, and so that means that the alleles at both genes are going to be the same, and we're told they're dominant.
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So this person has only dominant alleles.
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So their genotype looks like this.
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Then the other person, the other parent, we're told, is homozygous recessive, which again, homo meaning same.
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So they have the same all alleleys at both genes, and we're told that those genes are all recessive.
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So their genotype looks like this.
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And then armed with that knowledge, we can then figure out the f1 and f2 generation.
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So we're going to start with the f1 generation, which is actually going to be very easy.
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So you see, when both parents are homozygous in this way or consider true breeding, that means they can only give one type of allele at each gene.
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So we don't even need a punnet square to figure out the f1 generation.
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And i'll show you how to do this.
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So we're going to start with one gene.
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We'll start with t since i've listed it first.
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This first parent, has only dominant t alleles, meaning that they can only give dominant alleles to their offspring.
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Whether they give the one on the left or the one on the right, it's going to be dominant.
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So all the offspring have to get a dominant t from that parent.
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And then when we look at the other parent, something similar.
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This parent only has recessive alleles, meaning that they can only give recessive alleles to their offspring, and all the offspring have to get a recessive from that parent.
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The whys are the same way.
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One parent can only give dominant, so all the offspring have to get a dominant from them.
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The other parent can only give recessive, so all the offspring have to get a recessive from them.
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So we end up with an f1 generation that is genotypically identical.
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They are all the same.
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They all have heterozygous genotype, assuming no crossover.
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So they're completely heteros, i guess, meaning hetero meaning different.
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So one dominant, one recessive allele at each gene.
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But when we move to the f2 generation, it gets a little more complicated because we don't have that easy way to figure it out, but we have to do a punnet square.
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So for the situation where we're looking at two genes, t and y, we need a 4x4 punnet square.
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And we know that the f1 generation is crossed, with itself.
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So we know that both parents are heterozygous.
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And once we've drawn out our planet square, we're going to write out the possible comedic combinations from these parents by finding, you know, what are the options for combining a t and a y together? so the way we do this is, first option is the first t with the first y, and i'll write that here.
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Or you can have the combination of the first t and the second y...