Suppose you are heterozygous for two genes that are located on different chromosomes. You carry alleles A and a for one gene and alleles B and b for the other. Be sure to list all the genetically different gametes that could form and indicate how frequently each type should be observed.

Video transcript

Hi everyone here's our next question. A plant is hetero cygnus. For two genes that are present on different chromosomes. The first gene determines flower color with alleles big P. For purple little P. White. The 2nd gene determines the height of the plant. With a leal's big T. Tall and little T. Short determine the different types of gametes that this plant can produce. Well, we note that it says the plant has jeans on two different chromosomes. So as long as those genes are on different chromosomes, we know that we need to pay attention to the principle of independent assortment. So as the chromosomes with these different alleles on them separate in mitosis to produce gametes, they separate independently of each other. So we imagine our parent here with two chromosomes on the chromosome with the genes for color. One chromosome has the dominant and one recessive here we're using the letters to symbolize the chromosomes with those values. And then we have the gene for height, one chromosome dominant, one chromosome recessive. So again, we know that these will assort independently of each other. Where with the gametes having just one copy of each. So are four types of gametes here we can have big P. Big T. The two dominant getting inherited together. Big P. Might combine with little T. Little P. With big T. Or little P. Little T together because they don't need to split up together. They can be in any particular order. So that's the principle of independent assortment. And that's a result of the fact that when they line up during my aosis to separate imagine the midline of the cell. They can line up. They could happen to have the chromosome with Big P. On the same side as the chromosome is little big T. And therefore the two recesses on the same side. Or they could line up the other way with big P. On the same side as little T. Little P. On the same side as big T. So because they can line up in any order. Then during mitosis, when these chromosomes physically separate, you end up with these different combinations of gametes. So here are four gamma combinations. And when we look at our answers we see that choice D. Shows all four of these combinations. So the answer for the different types of gametes this plant can produce is Choice D. Big P. Big T. Big T. Little T little P. Big T. And little P. Little T. See you in the next video