How do we know that Drosophila utilizes a different sex-determina...

Question

How do we know that Drosophila utilizes a different sex-determination mechanism than mammals, even though it has the same sex-chromosome compositions in males and females?

Accepted Answer

Hey, everyone. Let's take a look at this question together in Drosophila, an X to a ratio of 1.0 or higher produces blank. Whereas an X to a ratio of 0.5 or lower produces, what is it? Answer choice. A sterile females and sterile males answer choice. B fertile females and sterile males answer choice C sterile females and fertile males or answer choice d fertile females and fertile males. Let's work this problem out together to try to figure out which of the following answer choice combinations best describes that X to a ratio found within the Drosophila flies. So we know that in Drosophila flies, we have this X chromosome autosomal balancing mechanism, which can be described as this X to a ratio, which is the X chromosome to autism ratio. And this exists because the Y chromosome does not impact sex. And so when it comes to the sex of the droop of flies, the autism determine the male gender and the X chromosomes determine the female gender. And when we say the autosome and the X chromosomes determining that male or female gender respectively, we are talking about the mount present of each, which can be represented in that X to a ratio. And so this X to a ratio of 1.0 or higher. So that X to a ratio is 1.0 or higher results in fertile females. Because we have a greater X number and we know that the X chromosomes determine the female gender, which means that when we have that X to a ratio of 0.5 or lower, we have fertile males. Because when the X to a ratio is 0.5 or lower, that means that we have more autosome. And we note that the Audis determine the male gender. So therefore, inro soila flies when we have that X to a ratio of 1.0 or higher, it produces fertile females and that X to a ratio of 0.5 or lower produces fertile males. So that means that answer choice d fertile females and fertile males is the correct answer. Since in those Drosophila flies where we have an X to a ratio, which is that X chromosome to autism ratio where we have an X to a ratio of 1.0 or higher. Meaning that the value for X is greater than the value of a, which means that there are more X chromosomes present than there are autosome. It results in fertile females. Where is the X A ratio of 0.5 or lower? Which means that we have more autosome present than X chromosomes, it results in fertile males. So answer choice D, fertile females and fertile males are the correct options for the blanks found within the question. So answer choice D is the correct answer. I hope you found this video to be helpful. Thank you and goodbye.

How do we know that Drosophila utilizes a different sex-determination mechanism than mammals, even though it has the same sex-chromosome compositions in males and females?

Key Concepts

Sex Determination Mechanisms

Drosophila Genetics

Chromosomal Composition vs. Sex Determination

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