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Homework Help: Genetics: Mapping and Recombinant Frequency

  1. Jul 7, 2010 #1
    1. The problem statement, all variables and given/known data

    Two homozygous plants are crossed and all offspring (F1) are yellow with long stems. A cross of the offspring (F1)produces the following phenotypes in the F2 generation:

    1,263 yellow, long stem
    1,196 white, short stem
    205 yellow, short stem
    195 white, long stem

    What information can be determined about the genes involved in the cross?

    Choose one answer.
    a. The genes are linked and are 14 map units apart.
    b. The genes are linked but you can tell how far apart they are from each other.
    c. The genes are linked and are 7 map units apart.
    d. The genes are not linked.

    2. Relevant equations

    3. The attempt at a solution

    1263 and 1196 are the parental type

    205 and 195 are the recombinant offspring

    Recombinant frequency= (205+195) / (1263+1196) * 100= 14%

    the genes are linked and are 14 map units apart
  2. jcsd
  3. Jul 7, 2010 #2
    Are you sure only the # of parental's goes in the denominator? :wink: Be careful.
    Your final answer is correct.
  4. Jul 7, 2010 #3
    Thanks....i actually forgot to put all of the progeny in the denominator...(205+195+1263+1196)
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