# THE BEAN LAB ALLELE FREQUENCY THE BEAN ALLELE

• Slides: 34

THE BEAN LAB: ALLELE FREQUENCY

THE BEAN ALLELE FREQUENCY LAB Purpose: The following pictures are a guide to show one example of how the allele frequency could change in a population due to a genetic disorder. Setup: The three types of beans (red [RR], pinto [Rr] and white [rr]) will be used to represent a population of individuals with a certain trait. If an individual has the recessive phenotype (rr) then there is a 50% chance of surviving to reproduce. Being a carrier of the trait (Rr) has no bearing on mortality. The 2012 -13 class has gone through the lab and developed a set of instructions to go along with the following pictures to help walk you through how to do the lab.

Slide #1 White, rr (16) Red, RR (16) Pinto, Rr (32) R and r frequency = 16 + 32 64 +64

Slide #2 White, rr (8) Red, RR (16) Pinto, Rr (32)

Slide #3 The Dating Game

Slide #4 Who got married to who from this Parent Generation (P)

Slide #5 The offspring of those couple, now known as the First Generation (F 1).

How did we get these numbers of beans?

How did we get these numbers of beans?

Slide #6 Red, RR (37) Pinto, Rr (54) White, rr (21)

Slide #7 Red, RR (37) Pinto, Rr (54) White, rr (11)

Slide #8

Slide #9

Slide #10

Slide #11 Red, RR (82) Pinto, Rr (92) White, rr (30)

Slide #12 Red, RR (82) Pinto, Rr (92) White, rr (15)

Slide #13

Slide #14

Slide #15

Slide #16 Red, RR (172) Pinto, Rr (166) White, rr (38)

IF WE CONTINUED ON THIS PATH, WHAT SHOULD THE NEXT SLIDE SHOW?

Slide #17 Red, RR (172) Pinto, Rr (166) White, rr (19)

DATA ANALYSIS

Days Bean Populaiton

Growth of Bean Population (10 Generations) Total Population of Beans 60000 50000 40000 30000 20000 10000 0 0 10 20 30 40 Days 10 Generation Forecast 50 60

What is happening to the overall bean population? Why is this happening to the OVERALL bean population? Could we expect this pattern to continue indefinitely? What factors could stop this pattern?

Days 4 generagtions of Beans Percentage of the Population

Allele Frequency over Generations 100 Perentage of Alleles 90 80 70 60 50 R Frequency 40 r Frequency 30 20 10 0 0 10 20 30 40 Days 10 Generation Forecast 50 60

OTHER QUESTIONS ON BEAN EVOLUTION * Will the white beans ever completely disappear at this rate? * What are some scenarios that could happen to cause the white beans to completely disappear? * The mechanism of evolution that this lab demonstrates is ______ because of ____.

OTHER MECHANISMS THAT COULD AFFECT ALLELE FREQUENCY

MIGRATION (GENE FLOW) New First Generation Reproduction Populations Original Population

MATE SELECTION Original Parent Pairs New Parent Pairs

SMALL POPULATION + CHANCE EVENT – DANGEROUS MUTATION Original Population Reproduction Population

INTRODUCTION OF A PREDATOR Original Population Fire Breathing Dragon who eats red beans for lunch