A pea plant that has the genotype RrGgwwdd is crossed to a plant that has the rrGgWwDd genotype. The R gene controls round versus wrinkled seed, the G gene controls yellow versus green seed, the W gene controls purple versus white flower, and the D gene controls tall versus short plants. Determine the following;


What proportion of the progeny are expected to have the genotype rrggwwdd?

The accompanying pedigree shows a family in which one child (II-1) has an autosomal recessive condition. On the basis of this fact alone, provide the following information.

What is the chance that among the three children in generation II who have the dominant phenotype, one of them is AA and two of them are Aa? (Hint: Consider all possible orders of genotypes.)

A pea plant that has the genotype RrGgwwdd is crossed to a plant that has the rrGgWwDd genotype. The R gene controls round versus wrinkled seed, the G gene controls yellow versus green seed, the W gene controls purple versus white flower, and the D gene controls tall versus short plants. Determine the following;

What are the phenotypes of each plant?

Go to the OMIM website (http://www.ncbi.nlm.nih.gov/omim) and locate the Search button at the top of the page. Use the search function to look up, one by one, the following three human hereditary diseases that are relatively common in certain populations: 'Tay–Sachs disease' (select OMIM number 272800 from the search results list); 'cystic fibrosis' (select OMIM number 602421 from the search results list); and 'sickle cell anemia' (select OMIM 603903 from the search results list). For each of these diseases, look through the information and provide the following details:

On which chromosome is the gene for the disease located?

Go to the OMIM website (http://www.ncbi.nlm.nih.gov/omim) and locate the Search button at the top of the page. Use the search function to look up, one by one, the following three human hereditary diseases that are relatively common in certain populations: 'Tay–Sachs disease' (select OMIM number 272800 from the search results list); 'cystic fibrosis' (select OMIM number 602421 from the search results list); and 'sickle cell anemia' (select OMIM 603903 from the search results list). For each of these diseases, look through the information and provide the following details:

What gene is mutated in the disease?

A pea plant that has the genotype RrGgwwdd is crossed to a plant that has the rrGgWwDd genotype. The R gene controls round versus wrinkled seed, the G gene controls yellow versus green seed, the W gene controls purple versus white flower, and the D gene controls tall versus short plants. Determine the following;

What proportion of the progeny are expected to have the genotype RrGGwwDd?

A pea plant that has the genotype RrGgwwdd is crossed to a plant that has the rrGgWwDd genotype. The R gene controls round versus wrinkled seed, the G gene controls yellow versus green seed, the W gene controls purple versus white flower, and the D gene controls tall versus short plants. Determine the following:

What proportion of the progeny are expected to be round, yellow, purple, and tall?