Sources of Genetic Diversity: A Web Learning
Created by: Susan H. Furr, University of Arizona, Department
of Molecular and Cellular Biology
Why do individuals look different? Spontaneous point
mutations are very rare and do not occur frequently enough to account
for the phenotypic differences among individuals. Remember that individual
differences give rise to natural selection via competition. If an individual
possesses a trait or traits that allow it to compete better for food,
shelter, mates, and nesting sites, then that individual will produce
more offspring because it is better nourished, is better protected,
lives longer and has mate(s) with which to reproduce more offspring.
The offspring will proliferate the genes for that individual's winning
trait(s). The differences among individuals provide the foundation for
In this lesson, you will learn about three genetic events
that give rise to biological diversity.
You should have already studied mitosis and meiosis
and have a good understanding of chromosome structure, homologous chromosomes,
fertilization, sexual vs asexual reporduction and diploid vs haploid
Describe the three processes that give rise to genetic variation
Predict the chromosome configuration arising from these three events.
Discuss why genetic variation drives evolution.
colored pencils - orange, blue, green, yellow
Color Coding - Throughout this interactive unit,
chromosomes use the following color codes: