In linkage mapping, how do we measure the distance between genes on a chromosome?  options:   A) The number of gametes used is proportional to the percent recombination in offspring.   B) The number of offspring produced is equal to the percent recombination during crossover.     C) The number of chromosomes resulting from crossover is equal to the distance the genes are apart in any one gamete.   D) The percentage of recombinant offspring is directly proportional to how far apart the genes are on the chromosome.

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Suppose researchers studied the first chromosome of a new species and mapped three genes of interest, indicated as a, b, and c. A three‑factor cross was performed and the number of gametes formed from the F2 generation was recorded in a table. Note that the order of genes in the table is arbitrary. Calculate the recombination frequencies for each given gene pair in map units. a+ b+ c+ a b c a b+ c+ a+ b c a b+ c a+ b c+ a b c+ a+ b+ c 173 176 35 33 11 10 3 1 After completing the gene mapping, the researchers treated individuals to induce inversions in the chromosomes. After treatment, another three‑factor cross was performed and the number of gametes formed from the F2 generation was recorded in a second table. Note that the order of genes in the table is arbitrary. a+ b+ c+ abc a b+ c+ ?+ b c a b+ c a+ b c+ a b c+ a+ b+ c 188 185 24 26 1 0 49 46 Calculate the recombination frequencies for each given gene pair in map units.

a) Are the genes linked? Please explain SPECIFICALLY how you can distinguish between linked and unlinked genes in this instance.  b) If the two genes are linked, calculate the % recombination between ser and thr. Show the formula used, as well as all of your calculations. c) Draw a single map illustrating the arrangement of the two genes on the chromosome with respect to each other and to the centromere of the chromosome. Make sure to map ALL three distances.

please complete all parts

Based on the data in Table 1, which individual(s) is/are heterozygous? Select all that apply   a) B IV-8 b) C IV-3 c) B IV-9 d) A IV-3

If two chromosomes of a species are the same length and have similar centromere placements and yet are not homologous, what is different about them? Choose 1: A) Genes are different B) Alleles are different C) Loci are different D) Nothing is different

Given the experimental set up below, and knowing the genes for stalked eyes (st) and black bodies (b) are on the same chromosome and recessive to wild type (un-stalked eyes and light body).  F2= a=489, b=56, c=497, d=49 A)  How many recombinant animals are in the F2 generation? B) ( How far apart, (as both a % recombination and in map units) are the stalk eyed and black bodied genes on this chromosome?

You would like to create new hybrid strains between various cereal grains of different ploidies. Which of the following crosses will yield a fertile hybrid? Select all correct answers. (note that tri=3, tetra=4, penta=5, hexa= 6, and octa=8) 0 0 0 0 pentaploid X triploid tetraploid X diploid octaploid X diploid hexaploid X diploid

I am trying to understand how linkage works, and I am hoping someone can explain how to solve the following problem: The diagram shows the linkage maps for four genes: A, B, C, and D. Which genes are most likely to undergo recombination?  Which genes are least likely to recombine? A.) A and D B.) C and D C.) B and C