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21:53um what he did and this is something that we're seeing actually in fruit flies because um the particular visual that I found was for fruit flies but he also did this for pea plants as well. Okay, [snorts] what you can do is you can take two true breeding um you can you can take a true breeding parent generation with different traits in a pea plant. You could say it's always purple and it's always tall. And I'm going to cross that with always white, always short. Okay? So now I have homozygous for two traits in my parents. I'm going to get some
22:35offspring that are again always purple, always tall because the tall part is going to work the same way as the purple part. And so everyone's going to be the same. But now I do a cross between those guys. Now, if you just do the mathematics, there's going to be 16 different choices instead of four because you're doing four by four across. And the mathematics is going to be such that I'm going to get a ratio of 9 to 3 to 3:1. Okay? Nine being I'm going to get the dominant parts of both. Three being I'm going to get the dominant of one, the recessive of the other. The other three being I'm going to get the do dominant of the second one, recessive of the first one, and only one out of 16. I'm going to
23:17recover that first generation of like recessive recessive. Okay. >> Mhm. It's it's bas it scales as you as you get to more traits here. The the the ratio of distribution effectively scales exactly accordingly. >> Yeah. And in this particular one, we're looking at fruit flies where um we're seeing eye color and body color. Okay. And eye color red is dominant and body color brown is dominant. >> Black for both is recessive. And so we're seeing 9 to 3 to 3:1. And you can go through the the punit square there and figure out how each of the alals was matched. And you can convince yourself that this is the case. >> That makes total sense.
23:57>> Okay. This is called the independent assortment law. meaning that the two different traits independently