In cockroaches wing length is determined by 2 alleles for a single gene (locus) and 3 distinct phenotypes are identifiable: short wings, medium length wings and long wings. Genetic crosses demonstrates that the medium wing length is produced in the heterzygote. (assume short is the p allele)
a) A sample of 800 roaches is collected from an apartment block and the wing lengths are measured. The researcher finds 269 roaches with long wings, 390 with medium length wings and 141 individuals with short wings. Calculate the phenotypic frequencies.
b) Using the phenotypic frequencies from a) calculate the frequency of each allele.
c) Calculate the gene frequencies of p (short wings) and q (long wings) from the actual numbers of each phenotype. How do these values compare wit those in b).
d) In an adjacent building the researcher collects a sample of 1369 roaches. Calculate the genotypic and phenotypic frequencies you would expect in this population. How many individuals would have long wings? What assumptions do you make in in performing this calculation?
e) The original sample of 800 individuals is taken back to the lab and allowed to reproduce under ideal conditions. In 6 months the population grows to 26,820. How many offspring will have medium length wings?
f) What assumptions do you make in doing the calculation in e)?
g) What type of growth does this represent? Calculate the rate growth r per month for this roach population.
In cockroaches wing length is determined by 2 alleles for a single gene (locus) and 3 distinct phenotypes are identifiable: short wings, medium length wings and long wings. Genetic crosses demonstrates that the medium wing length is produced in the heterzygote. (assume short is the p allele)
a) A sample of 800 roaches is collected from an apartment block and the wing lengths are measured. The researcher finds 269 roaches with long wings, 390 with medium length wings and 141 individuals with short wings. Calculate the phenotypic frequencies.
b) Using the phenotypic frequencies from a) calculate the frequency of each allele.
c) Calculate the gene frequencies of p (short wings) and q (long wings) from the actual numbers of each phenotype. How do these values compare wit those in b).
d) In an adjacent building the researcher collects a sample of 1369 roaches. Calculate the genotypic and phenotypic frequencies you would expect in this population. How many individuals would have long wings? What assumptions do you make in in performing this calculation?
e) The original sample of 800 individuals is taken back to the lab and allowed to reproduce under ideal conditions. In 6 months the population grows to 26,820. How many offspring will have medium length wings?
f) What assumptions do you make in doing the calculation in e)?
g) What type of growth does this represent? Calculate the rate growth r per month for this roach population.
