In this chapter, we focused on the Mendelian postulates, probabil...

Question

In this chapter, we focused on the Mendelian postulates, probability, and pedigree analysis. We also considered some of the methods and reasoning by which these ideas, concepts, and techniques were developed. On the basis of these discussions, what answers would you propose to the following questions:

How was Mendel able to derive postulates concerning the behavior of 'unit factors' during gamete formation, when he could not directly observe them?

Accepted Answer

Hi everyone. Let's take a look at this practice problem. Together we have the number of gina types produced in the F. One and F. Two generations of Mendel's mono hybrid crosses revealing how one trait is transmitted from generation to generation was blank and blank respectively. So the problem is asking for the number of gina types produced in the F. One and F two generations. So we need to know what Mandel's mono hybrid crosses would have looked like. Now recall that genotype is the genetic makeup and it's represented by the alleles. Also recall that the parents in Mendel's mono hybrid crosses would have been true breeder, meaning they both would have had different gina types. But all when they made it, all their offspring would have had the same phenotype. So let's do a mono hybrid cross example together and take a closer look at this. And we're going to take the trait of height implants. So big T. Will represent our tall a little and little T. Will represent our short a little. So our parents as in Mendel's cross would have been true breeder. So we would have a big T. Big T crossed with a little t, little T plant. So we need to do a Punnett square to determine the F one offspring. So we'll have big T. Big t little t little T. And our results will be the following. Now we can see that all offspring are actually the same And the offspring of the parents are the F one generation and they are all big T. Little T. So they are all the same genotype. So there's only one genotype in the F one generation. And that is the first part of our answer. Now we need to determine the jena types in the F. Two generation and that's done by taking a cross between big T. Little T. So self mating The F. one Generation. So that will look like big T. Little T crossed with another big T little T. Now let's do a punnett square for this. So we have big T. Big T, little T little T. Big T. Big T. And we can see that the offspring of that cross have a 1 to 2 to one ratio. There is one big T. Big T, two big T, little T and one little T. Little T. And so this is three different gina types And then the results, this is our f. two generation. And so that's going to be the second part of our answer is three. So let's reread the problem. The number of Jenna types produced in the F. One and F. Two generations of Mendel's mono hybrid crosses revealing how one trait is transmitted from generation to generation was one and three respectively. So that will be answer C. 123. So C. Is our correct answer. Alright everyone, I hope you found this helpful and I will see you for the next practice problem

Key Concepts

Mendelian Genetics

Unit Factors (Genes)

Probability in Genetics

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