Natural Selection
Survival of the fittest (define it)
What is organisms with the best traits survive AND reproduce?
When a large population is drastically reduced by a non-selective event such as a natural disaster.
What is the bottleneck effect?
The initial stage of development for multicellular organisms.
What is an embryo?
Scientists believe we are in the middle of the _______ mass extinction.
What is 6th?
Change in the genetic makeup of a population over time; descent with modification
What is evolution?
The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits
What is artificial selection?
All copies of every type of allele in a population
What is a gene pool?
A period of little or no morphological change within a species (lineage) over a long period of time.
What is stasis?
Reduced hybrid viability
Reduced hybrid fertility
Hybrid breakdown
What are post-zygotic barriers ?
Proposes that RNA could have been the earliest genetic material
What is the RNA World Hypothesis?
Favors one extreme phenotype in a population.
What is directional selection?
The transfer of alleles into or out of a population due to fertile individuals or gametes
What is gene flow?
Structures that are conserved even though they no longer have a use in present day organisms.
What are vestigial structures?
Species breed at different times of the day, year, or season
What is temporal isolation?
The frequency of the homozygous recessive genotype.
What is q2?
Favors unique and showy traits in order to attract a mate
What is sexual selection?
Forms new alleles
What are mutations?
2 pieces of evidence that supports the endosymbiotic theory.
What is the mitochondria and chloroplast have two membranes?
What is the mitochondria and chloroplast have their own circular DNA?
What is the mitochondria and chloroplast have their own ribosomes?
What is the mitochondria and chloroplast are capable of replicating without the cell?
When evolution occurs rapidly after a long period of stasis
What is punctuated equilibrium?
Two clades that emerge from the same node
What are sister taxa?
Draw and label a graph for each type of selection.
What is 3 correct graphs?
Stabilizing - peak in the center
Directional - peak moves in ONE direction
Disruptive - TWO peaks one on each side
The result of many fixed alleles in a population.
What is less genetic diversity?
Similarities in DNA and amino acid sequences
What are molecular homologies?
If a new habitat or niche becomes available, species can diversify rapidly
What is adaptive radiation?
All 5 conditions that need to be met for Hardy Weinberg equilibrium.
What is...
1. Random mating
2. Large population
3. No migration (no gene flow)
4. No mutations
5. No natural selection