If the dpy11 and unc31 genes are linked on the same chromoso

If the dpy-11 and unc-31 genes are linked on the same chromosome, how many phenotypes would the F_2 progeny show? If the two genes are on different chromosomes and therefore independently assorting, how many phenotypes would you see in the F_2 worms? List the phenotype(s). Strawberry plants have varieties that flower when the days are still short, and other varieties that flower only when the days get longer. The long-day allele is dominant to the short-day allele. You\'d like to test whether or not this gene is inherited in a Mendelian fashion. When you cross between heterozygous plants and count the offspring in the F_1 generation, this is what you find: 85 plants with no flowers on short days and 35 plants with flowers on short days What would you expect the ratio of phenotypes be? What is your Chi squared value? Show your work What does this mean?

Solution

2. Linked genes tend to inherit together for the next-generations. No crossing over ororoccurs independent assortment occurs. No new characters appear. Where as gegenes are on different chromosomes, they are non linked. Crossing over or independent assortment takes place. New characters appear along with parental characters. So dpy-11 & unc-31 present on same chromosome, they are linked and give only parental characters. Only 2 phenotypes appear. If the said genes present on different chromosomes, they give 4 different phenotypes

3. a. Heterozygous long day representing as Ll. When crossing or hybridization occur between these genes

Ll x Ll ----------> 3:1 is the phenotypes ratio. Three are long and one is short.

Chi square value can be calculated by using the formula.

(O-E)^2/E

O = observed phenotypes; E = Expected phenotypes