Question

For each of the following pages of questions use probability and/or branching to solve. Do NOT use dihybrid Punnett squares. Show your work for full credit. 2. You are interested in breeding dragonflies and are studying three different autosomal traits. The wild type alleles have short antennae (A), green thorax (T) and black eyes (E). Each of these genes also has a mutant, recessive allele: long antennae (a), yellow thorax (t) and red eyes (e). These three genes are located on different chromosomes and therefore sort independently.

a. You have true-breeding dragonflies with short antennae, yellow thorax and black eyes and other true-breeding dragonflies with long antennae, green thorax and red eyes. You cross them and obtain the F1 progeny.

i. Write out the genotypes of the following individuals:

1. true-breeding short antennae, yellow thorax, black eyes: _____________________

2. true-breeding long antennae, green thorax, red eyes: ____________________

3. F1 progeny: ________________________

b. For the following questions you cross the F1 progeny to a dragonflies with the genotype AaTTee. State the probability the cross results in following (treat each question independent of the other questions):

i. A progeny with the genotype aaTTee? ________________________ Is the progeny with the genotype aaTTee true-breeding, yes or no?

ii. A progeny with the genotype AaTtEe or aaTTee? ________________________

iii. A progeny with all dominant phenotypes? ________________________

iv. A progeny that is heterozygous for all three genes? _________________

v. Are the answers to iii and iv the same, why or why not?

Answer 1