BIOL 2050 Chapter 4: Module 5 - Extension of Basic Concepts
80 views11 pages
Document Summary
4. 3 additional factors at a single locus can affect the results of genetic crosses. Dominance although an individual organism possesses two diff alleles for a characteristic, the trait encoded by only one of the alleles is observed in the phenotype. Heterozygote possesses same phenotype as a homozygous. Dominance affects the way genes are expressed (phenotype), not the way that they are. Complete and incomplete dominance: ex: potential flower color ranged from red to white, a1a1 = red pigment (red flowers, a2a2 = no pigment (white flowers) If the heterozygote (a1a2) produces same amount of pigment as a1a1 (red flowers) , then the a1 allele displays complete dominance over the a2 allele red is dominant over white. If the heterozygote produces no pigment (white flowers), then the a2 allele displays complete dominance white is dominant over red. If the heterozygotes phenotype falls in bw the phenotypes of the two homozygotes (red and white = pinkish flowers), this is incomplete dominance.
Get access
Grade+
$40 USD/m
Billed monthly
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
10 Verified Answers
Class+
$30 USD/m
Billed monthly
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
7 Verified Answers
Related Documents
Related Questions
Dr. sisko studies the flowering plant Mimulus cardinalis in an experimental population of size 1000 that grows in acidic soil. The color of the flower in this plant is determined by a single locus with two co-dominant alleles A1 and A2. Laboratory observations show that seeds from red and pink flower plants survive with equal success in the acidic soil but seeds from plants with white flowers (A2A2) have decreased fitness with a selection coefficient of s=0.2
Phenotype | Red (A1A1) | Pink (A1A2) | White (A2A2) |
# plants (adults) | 200 | 300 | 500 |
Fitness | 1.0 | 1.0 | 1-s |
1) Calculate the allele frequencies in the next generation before selection.
2) Calculate the allele frequencies in the next generation after selection.
3) Calculate the genotype frequencies in the next generation after selection.