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Lab 3: Hardy-Weinberg Equilibrium

  • Page ID
    18389
  • Name: ______________________________

    Section: _____________________________

    Student ID#:__________________________

    Please read the section of your assigned textbook that covers Hardy-Weinberg Principle of Equilibrium. It will explain how this equation is used to determine the percent of a population that carries heterozygous traits, and how these unexpressed traits can appear in future generations.

    • \(q\)= Dominant Trait
    • \(r\)=Recessive Trait
    • \(q\)=Subordinate Dominant Trait

    These formulae assume stability in population:

    \((q+r)^{2} \qquad=\quad q^{2}+2 q r+r^{2}\) \(\begin{array}{l}{\text { if } q=.5 \& r=.5, \text { then } q^{2}=25, r^{2}=.25 \& 2 q r=.50} \\ {\text { If } q=.4 \& r=6, \text { then } q^{2}=16, r^{2}=.36 \& 2 q r=48}\end{array}\)

    \((q+p+r)^{2}=q^{2}+p^{2}+r^{2}+2 p q+2 p r+2 q r\)\(\begin{array}{l}{\text { If } q=3, p=3, \& r=4 \text { then next generation will show }} \\ {q^{2}=.09, p^{2}=.09, r^{2}=.16,2 p q=.18,2 p r=.24, \& 2 q r=.24} \\ {\text { or } q=.51, p=.33, \& r=16}\end{array}\)

    1) What will your distributions be in the second generation if \(q=.69 \ \& \ r=.31\):

    2) What will your distributions be in the second generation if \(q=.31 \ \& \ r=.69\):

    3) What if \(q=.33, \ p=.34, \ \& \ r=.33\), what will be your populations and their expression in the next generation?

    4) What if \(\mathrm{q}=.9 \ \mathrm{p}=.05, \ \& \ \mathrm{r}=.05\), what will be your populations and their expression in the next generation?

    5)a) In the current generation, \(q=.9 \ \& \ r=.1\). If q is completely selected against, what will the distributions be in the next generation? (equation)

    b) What will these distributions be if r is completely selected against? (essay)

    6) What is the relationship between the dominance of a trait, and its rate of survival if it is selected against by either natural or artificial selection? (essay)

    7) In the current generation the distribution of traits is \(q=.4, \ p=.4, \ \& \ r=.2\). What will the distributions be in the next generation? (equation)

    b) Given your answer to 7, what would you expect if during the second generation q is completely selected against, what will the third generation‟s distribution look like? (essay)

    c) Given your answer to 7, what would you expect if during the second generation p is completely selected against, what will the third generation‟s distribution look like? (essay)

    d) Given your answer to 7, what would you expect if during the second generation r is completely selected against, what will the third generation‟s distribution look like? (essay)