Hardy Weinberg Lab Activity
Answer all of the questions in this document. Please change your font color to blue or red. Save and submit this document with your answers included with an appropriate file name in either Word 97-2003 format (.doc) or rich text format (.rtf). John Adams would name his file for this assignment Adams_Lab10.doc. Now as you are not Mr. Adams you will use YOUR name in the file name.
Use your textbook, notes and these websites to answer the pre lab questions.
http://www.mansfield.ohio-state.edu/~sabedon/biol1509.htm
http://www.k-state.edu/parasitology/biology198/hardwein.html
http://nhscience.lonestar.edu/biol/hwe.html
Pre Lab Questions
1. In a population of 100 flies you gathered the following information: 15 Homozygous Black, 30 Heterozygous Black, 55 Homozygous Brown. Using this information fill in the chart below and answer the questions
| Genotype | Number in Population | Total # B
alleles |
Total # b
alleles |
| BB | |||
| Bb | |||
| bb | |||
| totals |
2. What percentage of the population is phenotypically Black?
3. Calculate the actual allele frequency of B. Provide a full explanation of your work .
4. Calculate the ESTIMATED allele frequencies of b and B– provide a full explanation of your work.
5. Why is there a difference between the actual and estimated frequencies?
Go to this sitehttp://www2.edc.org/weblabs/WebLabDirectory1.html to run simulations to test the Hardy Weinberg principles. Answer the following questions as you work through the rest of this document.
First click on the oval The Hardy Weinberg Equation. It may automatically install Adobe Shockwave – let it.
Click on the oval Enter the Web Lab. Click enter on the next screen.
6. Fill in the following table by changing the values of p to match the far left column.
| P value in % | P2 | 2Pq | q2 |
| 100 | |||
| 70 | |||
| 50 | |||
| 25 | |||
| 10 |
7. What value of P gives you the most heterozygous individuals?
Click on Next until the very large punnett square is filled in. Use the data from that table to fill in the following table.
8.
| Genotype | Number in Population | Total # A
alleles |
Total # a
alleles |
| AA | |||
| Aa | |||
| aa | |||
| totals |
Calculate the Actual A allele frequency.
Calculate the Estimated a allele frequency.
You will need the numbers from the above tables to continue through the exercise.
Click on the “1” and “2” to read more about Hardy Weinberg. Then click on Next.
9. What is non random mating? What effect does this have on the population? Does non-random mating favor one allele over another? Explain your answer.
Click through and read about the 5 Hardy Weinberg parameters. Then you will be able to go to lizard island … read and then click on the notebook. Using the information the scientists collected, fill in the table below. You only will know the total population and the number of homozygous recessive individuals. You must estimate your P and q values then use the P2 + 2PQ + q2 = 1 to determine the population numbers for AA and Aa.
10. Fill in the table below
| Genotype | Number in Population |
| AA | |
| Aa | |
| aa | |
| totals |
With only the population numbers, you will have to estimate the frequencies of P and q.
What is the estimated frequency of the a allele? Show your work.
What is the frequency of the A allele? Show your work.
By knowing the values for P and q, calculate the number of homozygous dominant and heterozygous individuals. Show your work.
Click through and read about Hardy Weinberg parameters and human blood types until you get back to lizard island.
11. What Hardy Weinberg factor is causing the increase in the recessive a allele? Explain your answer.
12. Will the A allele ever disappear? Why or why not?
