Solved by a verified expert:Please answer each of the following questions. Unless specificallystated otherwise, you must explain your reasoning in fullsentences and show your work to receive credit.1.Briefly explain why each of the following traits made peas aneffective model system for genetic research. For each trait,illustrate your argument by giving an example of a species or typeof organism that lacks such a trait and would therefore makegenetic research more difficult or intractable.a. Can be used in controlled crossesb.Short generation timec. Existence of “true-breeding” (i.e., inbred or homozygous)linesd.Produces large number of progeny2.Mendel’s famous crosses between “true-breeding” Pisum sativumwith yellow and green peas and subsequent self-crossing of the F1generation produced strong evidence for particulate inheritanceand undermined prevailing views based on blending inheritance.Consider an alternate outcome in which the results of these crosseswere consistent with blending inheritance. What phenotypes wouldhave been expected in the F1generation and in the F2 generationunder a blending model of inheritance?3.A mutant cucumber plant has flowers that fail to open whenmature. Crosses can be done with this plant by manually openingand pollinating the flowers with pollen from another plant. Whenclosed × open crosses were performed, all the F1 progeny wereopen. The F2 plants were 145 open and 59 closed. A cross ofclosed × F1 gave 81 open and 77 closed offspring. Describe thegenetic basis of inheritance for this trait, including the evidencethat led to your conclusions. 4.As a Drosophila research geneticist, you keep stocks of fruit flieswith specific genotypes. You have a fly that has normal wings(dominant phenotype). Flies with short wings are homozygous fora recessive allele of the wing-length gene. You need to know if thisfly with normal wings is true-breeding or heterozygous for thewing-length trait. Assuming you have access to flies of knowngenotype, describe two different types of crosses that could beperformed to determine the genotype of the mystery fly. For eachcross, what are the expected results for each of the two possiblegenotypes?5.Briefly explain why the following statement is either true or false:All genes are made of DNA and code for proteins.
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