1. Monday, September 10, 2012

2. Purpose of H-W Principle:
The Hardy-Weinberg Principle provides a baseline for comparison & determines whether or not gene frequencies have changed in a population and thus whether (micro)evolution has occurred.

3. Hardy-Weinberg Assumptions
Very large population size
No migration
No net mutation
Random Mating
No natural selection

4. Hardy-Weinberg Equations:
p = frequency of allele 1 in gene pool
q = frequency of allele 2 allele in gene pool
Frequencies can be expressed as decimals (0.4) or percentages (40%)
p + q = 1

5. Hardy-Weinberg Equations:
Allele frequency is used to predict genotype frequency (%) for a randomly mating population
Homozygous for allele 1 = p • p = p2
Homozygous for allele 2 = q • q = q2
Heterozygous = p • q or q • p = 2pq
p2 + 2pq + q2 = 1

6. Hardy-Weinberg Lab
Instructions dictate initial allele frequencies of:
p = 0.5
q = 0.5
If there are 28 Teddy Grahams in your population, how many should be pp? pq? qq?
Explain how you determined your answer.

7. Teddy Grahams mate randomly. All bears are equally attractive.

8. Though they live a good life, it is short
Though they live a good life, it is short. After having 2 babies, they die keeping the population size constant .

9. All bears are equally in danger of predation due to their yumminess

10. Teddy Graham Genetics
Today you will be helping Teddy Grahams to procreate.
Reminder of the genetic rules:
When honey and honey mate, 2
Honey are born
When honey and chocolate mate,
2 speckled are born
When honey and speckled mate,
One honey and one speckled are born
When chocolate and speckled mate,
One chocolate and one speckled are born

11. When Speckled and Speckled mate
Use the allele cards. Each speckled has a p and a q allele
Pick one allele for each parent to give
This determines the genes of the first offspring
Return the cards to the parent and pick again for the second offspring

12. Allow 5 generations to mate.
Fill in the data chart and calculate allele frequencies at the end of 5 generations
Conduct a Chi Square test to see whether the number of bears of each type you expect to have if allele frequencies did not change, differs from the observed (actual) number of each type you have