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In fruit flies, body color is either tan or ebony; this trait is controlled by a single autosomal gene, with the dominant allele T = tan, recessive allele t = ebony.You sample a large population of randomly interbreeding flies and find that out of 100 flies, 91 have a tan body and 9 have an ebony body.  Assuming that the population is in Hardy-Weinberg equilibrium, how many of the tan flies should be heterozygous (genotype Tt)?

Which feature would you adjust to focus on the specimen?

You examine dishes of tobacco seedlings, noting seedling color.   Each dish represents offspring from a single genetic cross.  You know that there is a single genetic trait involved in chlorophyll production that creates the color difference that you are observe.  Use the following designations for the alleles:G = chlorophyll production; green seedling (dominant)g = no chlorophyll production; white seedling (recessive) In one dish you count no green seedlings and 91 white seedlings.  What are the most probable genotypes of the parents?

The following symbols are used in this narrative:G = allele for green pea podsg = allele for yellow pea podsIn his studies Mendel looked at the inheritance of pea pod color.  When he performed monohybrid crosses (Gg x Gg) and then grew the offspring he found the following:428 plants making green pods152 plants making yellow podsPerform a chi-square test comparing the predicted numbers for Gg x Gg with his results (you will have to calculate the predicted numbers yourself). Table of Chi-Square Numbers Degrees of Freedom 90% 80% 70% 50% 30% 20% 10% 5% 1% 1 0.016 0.064 0.148 0.455 1.074 1.642 2.706 3.841 6.635 2 0.211 0.446 0.713 1.386 2.408 3.219 4.605 5.991 9.210 3 0.584 1.005 1.424 2.366 3.665 4.642 6.251 7.815 11.341  The chi-square (χ2) when you compare your result to the expected result is:

Shown below are:

Shown below are:

The functional group below is a/an _______ group.

The functional group below is a/an _______ group.

In the fruit fly Drosophila melanogaster, eye color is influenced by an X-linked gene.  Also, females are XX and males are XY for sex chromosomes.  The alleles for eye color work as follows: XR = dominant; red eyesXr = recessive; white eyesY = Y chromosome; male, no eye color gene on this chromosomeYou examine a vial of 100 flies that are all offspring from a single genetic cross. You find both red-eyed males and white-eyed males but only red-eyed females.  The genotypes of the parents were apparently:

The cells below are both _ and _ .