Download BIOLOGY CONTENT STANDARDS REVIEW

BIOLOGY: EVOLUTION REVIEW
The frequency of an allele in a gene pool of a population depends on many factors and may be stable or unstable
over time. As a basis for understanding this concept:
Students know why alleles that are lethal in a homozygous individual may be carried in a heterozygote and
thus maintained in a gene pool.
1. Compare and contrast the terms homozygous and heterozygous.
2. Explain how lethal alleles are maintained in a gene pool (e.g., Tay Sachs disease).
Students know variation within a species increases the likelihood that at least some members of a species
will survive under changed environmental conditions.
3. What is genetic variation?
4. Explain how genetic variation is essential when it comes to the survival of a population.
Evolution is the result of genetic changes that occur in constantly changing environments. As a basis for
understanding this concept:
Students know how natural selection determines the differential survival of groups of organisms.
5. What is Natural Selection? How does Natural Selection work?
6. Does Natural Selection work on a phenotype or genotype?
7. What is selective pressure and how does it relate to Natural Selection?
Students know a great diversity of species increases the chance that at least some organisms survive
major changes in the environment.
8. Explain how variation within a species increases the chance that some organisms would survive a major
environmental change (i.e., selective pressure). Provide at least one example.
Students know the effects of genetic drift on the diversity of organisms in a population.
9. What is genetic drift? How does genetic drift relate to biological evolution?
Students know reproductive or geographic isolation affects speciation.
10. Define geographic isolation, reproductive isolation, species,
terms/processes relate?
and speciation.
How do these
Students know how to analyze fossil evidence with regard to biological diversity, episodic speciation, and
mass extinction
11. What is a fossil? How are fossils formed?
12. Explain how the fossil record provides evidence of biological diversity (that existed in the past),
episodic speciation, and mass extinction.