In the cross shown here, involving two linked genes, ebony (e) and claret (ca), in Drosophila, where crossing over does not occur in males, offspring were produced in a 2 + : 1 ca : 1 e phenotypic ratio: These genes are 30 units apart on chromosome III. What did crossing over in the female contribute to these phenotypes?

Hello everyone and welcome to today's video. So the following image shows the locations of genes X Y and Z in a chromosome. If the distance between genes, Y and Z is 10 units and the distance between genes X and Y is 30 units. What is the distance between genes X and Z? And this is more of a math problem than a biology problem because if we're told that the distance between Y and Z is 10 units and the distance between X and Y is 30 units, then we simply need to add these two and we will obtain the total distance between X and Z which is going to be 40 units and that is going to be represented by answer choice. C I really hope this video helped you and I hope to see you on the next one.