BIO 325 Genetics First Exam - BIO 325 Genetics 1st Exam Question with Answers Latest Version

KEY BIO 325 Genetics First exam. Name_____________________¬¬¬¬¬____________ UTEID________________________________ Read each question very carefully and make sure you are answering the question asked. Please make your answers are extremely clear and as short as possible. Place a circle or box around your final answer. You will not get credit if nothing is circled or boxed. Circle EVERY answer, not just the multiple guess question. You may use a calculator if necessary. If you want to have the possibility of a regrade, write your answers in pen. The test is over at 10:45. GOOD LUCK! --------------------------------------------------- Average = 84  1. A goldfish is homozygous dominant O for the gene for orange pigmented scales, but it is also homozygous for the dominant B allele of a gene that causes black scales. Any goldfish with a dominant B allele has black scales. A second goldfish is homozygous for the recessive o allele of the orange gene and makes no orange, but it is homozygous bb at the black scale gene. This fish is white. What is the genotype of the F1 from a mating between these two goldfish? (3 pt) Parents OO BB x oo bb F1 are dihybrid Oo Bb What is (are) the phenotype(s) of the F1? (3 pt) All Black because B is dominant epistatic to O. What relationship do the O gene and B allele have? (3 pt) The B allele is Dominant Epistatic to the O gene. What fraction of the F2 progeny of these two fish will have orange scales when you cross F1 siblings? (Express your answer as a fraction.) (3 pt) A Punnet square will give you the answer to fraction of orange goldfish. Any genotype with O- bb will be orange. 3/16