Question about Mendel Genetics

[holdmystethoscope]

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I am super confused about mendel's law. Please help:
1) the punnet square that predicts colors and shapes of the beans, are these happening during during meiosis ii?
2) All these color/shape alleles are located in sex chromosomes right? Or I guess what I am asking let's say BB is black hair homo and bb brown hair hetero. How do they relate to XX and XY?
3) What are the actual difference between first and second law. To me the first one deals with less allele (just color) and second one deals with different alleles (color and shapes)

 

[victorias]

1. The punnett square is showing what the genotype would be for the offspring if particular combinations of gametes come together in the fertilization process. It is assuming that at that point, gametes have been formed, so meiosis I and II have been complete.

2. If a punnett square is showing the alleles like AA, Aa, aa, then by convention of how these are written, we can say that the alleles are on autosomal chromosomes. If alleles are on the sex chromosome there is a different convention of writing them like X^a, X^A etc - these would be commonly seen in examples of sex linked disorders.

3. Mendel's law of segregation states that alleles segregate singly into gametes and that only one copy of each gene is passed onto the offspring. This happen in meiosis II where the sister chromatids split apart in anaphase II.

Mendel's law of independent assortment states that alleles assort independently of one another meaning that the the way in which alleles for gene A split into the daughter cells (gametes) does not influence the way in which alleles for gene B split. This can happen in Meiosis I when tedrads form in prophase I and participate in recombination and then they line up randomly on the metaphase plate. There is exception to this law when genes are said to be linked meaning that if genes are close to each other on the same chromosome, they are likely to assort together and end up in the same daughter cell - there is a lower likelihood of recombination for these genes.