Which of Mendel's postulates are illustrated by the pedigree that...

Question

Which of Mendel's postulates are illustrated by the pedigree that you constructed in Problem 3? List and define these postulates.

Accepted Answer

everyone. Let's take a look at this practice problem. Together we have Mandel's 3 to 1 fanatic ratio and the F. Two generation led him to postulate blake will recall that a postulate is also a law and Mandel had three of them. He had the law of dominance, the law of segregation and the law of independent assortment. So we know that our answer should be one of these three. Now this 3 to 1 phenotype IQ ratio in the F. Two generation. Exactly what is that recall that Mendel's experiments? The F two generation was the cross of two hybrid from the F. One generation. And now when this occurred, the offspring of the F. Two generation occurred in a 3 to 1 ratio, meaning there was three dominant offspring for every one offspring. So that's the ratio that's referred to in the practice problem. So let's go ahead and take a look at our options. We have a unit factors, recall that unit factors are also known as sales. This is a simple term, it's definitely not one of Mendel's laws and therefore we can eliminate it. Let's go ahead and jump to option C dominance. Now this is one of Mendel's laws but let's recall what it is. And that is that a dominant Aloul will mask a recessive allele. So dominant lil's are expressed over recessive littles And while this does explain why three of the offspring and the F2 generation are fanatically dominant. It does not explain why and how one of the offspring is phenol typically recessive. So therefore we can eliminate options, see if we take a look at option D. Recessive nous. This simply refers to the fact that a recessive A lil is gonna be masked by a dominant. So basically the option of opposite of option C. However, it's not a law and therefore we can eliminate it as well. Lastly we have be segregation. This is one of Mendel's laws and it's the only one that is a law. Therefore we know that this must be our answer. However, let's recall what the law of segregation is and that is for each trait an organism has. There are two lil's but only one little has passed on in each gamete. The hybrids of the F one generation separated into dominant and recessive alleles. But then in the F two generation, both alleles are expressed in that 3 to 1 ratio. So again be segregation is our answer. Alright, everyone. I hope you found this helpful and I'll see you for the next practice problem

Which of Mendel's postulates are illustrated by the pedigree that you constructed in Problem 3? List and define these postulates.

Key Concepts

Mendel's Law of Segregation

Mendel's Law of Independent Assortment

Dominance and Recessiveness

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