4 square miles of land is separated into sections that each an area of 1/2 square mile.How many sections are there?

Step-by-step explanation:

A. In the equation, the n represents the no. of genes involved. If n =1, a single gene is responsible, then X= (1/4)^1= 1/4 offsprings will be of one parental type.

B. Out of 50,000 plants, 1 out of 500 had maize phenotype and another 1 out of 500 terosinte phenotype.

So 1 in 500 so how much in 50000?

1*50000/500 = 100.

100 plants are of terosinte and 100 are of maize phenotype. The rest plants have recombinant phenotype. The exact phenotypes cannot be told from the given information.

C. According to formula, if 2 genes are involved, then 1 in 16 will be of one parental type. If genes 4 are involved, then 1 in 4^4= 1 in 256 will be of one parental type. If 5 genes are involved then it will be 1 in 512 plants will be of parental type. On the question, every 1 in 500 plants have one parental type. Hence Dr.Beadle concluded that 4 or 5 genes are involved in the phenotypic difference.

D. Genes code for all physical characteristics of an organism. Changes to genetic material can result in far reaching consequences in one or more particular metabolic pathways, this results in different phenotype compared to parents. Genes can mask other genes effect, complement it, or supplement it resulting in diverse response. The genes can also act in additive manner called quantitative genetics. Certain gene upon expression can block other genes expression, called epistasis. Such diverse mechanism can result in very different looking plants even with changes in small number of genes.