Evolution Test Flashcards
Darwin noticed that organisms were suited to ______________ in the environments in which
they live. The most successful organisms live long enough to _________________. Their
survival is often due to ____________________ that organisms possess. This ability to survive
and reproduce is what Darwin called “_______________”
adapt;
reproduce;
traits;
natural selection
What is Natural Selection?
the process by which evolution occurs, sometimes referred to as “survival of the fittest”
- the process that more suitably adapted organisms will survive and reproduce, passing on their traits to their offspring
- those not well adapted will die, not producing offspring
What kind of evidence do scientists use to support the theory of evolution?
- embryological evidence
- fossil evidence
- molecular evidence
- homologous structures
- vestigial structures
Fossil Evidence
history of life as documented by fossils
DNA/biochemistry
often in evolution, DNA sequences are compared to show how different species are related
Embryology
Study of embryos
What are vestigial structures?
structures/features on an organism that have lost much/all original function through evolution (ex: human appendix)
What are homologous structures?
similar structures that are shared by multiple organisms with differing functions (ex: bird wing, dolphin fin, human arm)
What are analogous structures?
differing structures are features on multiple, separate species similar in function (bird wings vs. insect wings)
What is Biogeography?
study of geographic distribution of plants and animals
Can organisms choose their adaptations?
No
Explain the peppered moth population before, during and after the industrial revolution.
Before: White moths made up majority of the population, because the trees were lighter (they can camouflage better)
During: Black moths became more prominent and common, because the smog blackened/darkened the trees (the black moths camouflage better)
After: White moths became more common, because the use of smog lessened (the trees were no longer darker)
What is a species defined by?
it is a group of similar organisms that can breed and produce offspring
What are the 3 types of natural selection?
- Stabilizing Selection
- Directional Selection
- Disruptive Selection
**Draw a graph of each and study the examples from your homework worksheet
What is genetic drift?
a change in the genes (alleles) of a population by random chance
What are 2 types of genetic drift? Explain.
- Genetic Bottleneck: a disaster killing many individuals in a population, causing a dramatic reduction of a population’s size and reduced genetic diversity
- Founder Effect: a few individuals colonize a brand new habitat,causing the new gene pool to have reduced genetic diversity
**Study your worksheet for examples of genetic drift (DO 1 PRACTICE PROBLEM IN IDENTIFYING WHICH TYPE IT IS)
What is speciation?
the process of forming new species from a species already in existence
What is reproductive isolation?
when two populations no longer interbreed
What are the 3 types of reproductive isolation?
- Geographic Isolation
- Behavioral Isolation
- Temporal Isolation
Give a definition or example for the 3 types of reproductive isolation
- Geographic Isolation: when two populations become separated by a physical barrier, such as rivers, mountains, or lakes
- Behavioral Isolation: when two populations become isolated by differences in courtship rituals or other behaviors
- Temporal Isolation: when two populations become isolated because they reproduce at different times or patterns
What is genetic equilibrium?
allele and gene frequencies do not change from generation to generation
What does the Hardy-Weinberg principle state?
In order for a population to have genetic equilibrium and to not have had any evolution it must have:
1. No selection
2. No mutation
3. No migration
4. Large Population
5. Random Mating
What are the 5 principles that can disturb genetic equilibrium?
- Natural selection
- Mutations
- Migration
- Small population
- Non-random mating
What does each part of the Hardy-Weinburg equation represent?
p + q = 1
- p represents the dominant allele frequency
- q represents the recessive allele frequency
p2 + 2pq + q2 = 1
- p2 (p squared) represents the homozygous dominant (GG)
- 2pq represents heterozygous (Gg)
- q2 (q squared) represents the homozygous recessive (gg)
What does q2 represent
homozygous recessive
What does p2 represent
homozygous dominant
What does 2pq represent
heterozygous
**Practice 2 questions with the Hardy-Weinburg equation
