# I am confused about the first question part B and C. How am I

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I am confused about the first question part B and C. How am I suppose to approach the question and show work? ATTACHMENT PREVIEW Download attachment 3 pages BICD100_HW1.pdf 1. 1 2 ? a) Is the trait dominant or recessive? b) What is the probability that the unborn child will be affected with the trait? c) If the expecting parents have a second child, what is the probability that the second child will be affected with the trait? d) What is the probability of their third child being affected if the second child is affected? e) Individuals 1 and 2 want many children. If they have 3 more children, what is the probability that at least 1 will be affected? 2. As you may know, the color of the nose of cats is under a strict genetic control: a pink nose (P) is dominant over a black one (p). You found a pink nose cat: a. What is/are the possible genotype(s) of the cat? b. How can you determine exactly its genotype through a genetic method? Draw the Punnett square for the different situations and define the ratio of the possible genotype and phenotypes. 3. A horticulturist is interested in producing new varieties of snapdragon with altered flower characteristics of possible commercial value. Wild-type snapdragon flowers are large (L) and red (R). Two new true-breeding varieties are produced, one with small flowers (ll), and one with cream-colored flowers (rr). Each of these variations is found to be caused by a recessive mutation in a single gene. The following crosses are done to test for linkage between the cream-colored flower mutation and the small flower mutation: small (llRR) X cream (LLrr) —> F1 (all large and red, LlRr) X small, cream (llrr) —> F2 as follows: 119 small, red (llRr) 127 large, red (LlRr) 135 large, cream (Llrr) 140 small, cream (llrr) Use the chi-squared test to determine whether the cream-colored flower mutation is linked to the small flower mutation. In your answer, include the value of chi-squared, the associated p-value, and your conclusion. 4. In the pea strains used by Mendel, differences in flower color, pea shape, and pea color were each controlled by a single gene. Purple flower color was dominant to white flower color, round peas were dominant to wrinkled peas, and yellow peas were dominant to green peas. Mendel crossed a true-breeding strain of peas with white flowers and round, green seeds to another true breeding strain with purple flowers and wrinkled, yellow seeds. The resulting trihybrids were then allowed to self-pollinate to produce a population. a. In the trihybrids, what color(s) were the flowers, and what were the colors and shapes of the peas? b. What proportion of the progeny had white flowers and round, green seeds? c. Of the progeny with these phenotypes (white flowers and round, green seeds), what proportion will be true breeding? d. How would the answers to the above parts be different if the first cross was between a true breeding strain with white flowers and wrinkled, yellow peas and another true breeding strain with purple flowers and round, green peas? 5. A cell during G1 of interphase has 16 chromosomes. How many chromosomes and sister chromatids will be found in the cell during the following phases? a) G2 of interphase b) Prophase II of meiosis c) Anaphase II of meiosis d) Metaphase I of meiosis e) Cytokinesis after meiosis II Read more

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