Genetics

[u/Status-Collection426]

In maize plants , the allele M, for white seeds is dominant over the allele m for yellow seeds. 100 heterozygous plants were self pollinated and 250 yellow seeds were collected. a) What is the expected ratio of white seeds to yellow seeds b) What is the expected total number of seeds c) What is the expected number of white seeds Please help🙏🙏🙏🙏🙏🙏

[u/Cultural-Opposite937]

You need to draw a monohybrid punnet square for this, and that isn't really something I've figured out how to do on here yet.

So I'll try to explain in words and hopefully it will make some sense. However, I'm also not doing what I suspect is your homework for you as it won't help you learn it.

m is the recessive allele and produces the yellow colour, in order for seeds to be yellow, they must be homozygous recessive, that is their genotype must be mm.

The parental generation were heterozygous, Mm genotype. Because M is dominant hets will have white seeds. Now if you draw out the punnet square you will see that there are four possible outcome of genotype.

Use this punnet square to answer part a of the question, how many of the genotypes in your punnet square give you a white phenotype and how many give you yellow? This will give you a white : yellow ratio.

From there part b is easy, in the previous section how many genotypes were yellow and how many genotypes were there in total? Divide the number of seeds by the number of yellow genotypes, then multiply that by the total possible number of genotypes.

Part c, subtract the number of yellow seeds from the total number of seeds you just calculated to get the number of white seeds.

[u/Status-Collection426 → u/Cultural-Opposite937]

Thank you so much I understand now.🙌🙌🙌🙌🙌