Evolution lab practical 1 Flashcards
Evolution
Descent with modification. Involves changes in allele frequencies over time
Natural selection
the selection for those phenotypes that are better adapted with the result that such phenotypes contribute more surviving offspring to the population than other phenotypes
When does evolution occur (5 factors)
- Mutation: produce variation in the gene pool
- Gene flow: frequency of genes in the gene pool may change due to immigration or emigration
- Natural selection: impact of the environment on the frequency of alleles
- Genetic drift: frequency of alleles in the gene pool may change by pure chance
- Nonrandom mating: if there is a mating preference in the population, the frequency of alleles in that population will change
Dichotomous key
A tool that allows the user to determine the identity of items in the natural world. They consist of a series of choices that lead to the correct name of the given item
Cladogram
A branching diagram showing relationship between a number of species. They focus on identifying common ancestry of related groups
Name the six kingdoms and give an example of each
Plants (trees), animals (human), protists (protozoa, algae), fungi (yeast), archeabacteria (crenarchaeota), eubacteria (e. coli)
How are scientific names derived
The first word is the genus the species belongs to. The second word is specific to the organism and is called the species epithet. The words are greek or latin
Castle-Hardy-Weinberg law
simple mathematical expression that establishes a point of reference in evaluating genetic changes in a population
Castle-Hardy-Weinberg formulas
p+q=1
p^2+2pq+q^2=1
Castle-Hardy-Weinberg conditions
- Mutations do not occur
- The population size is large
- The population is isolated from other populations of the same species (no immigration or emigration occurs)
- No selection takes place (the genotypes are equally viable and fertile)
- Mating is random
Taxonomy
The study of the principles, procedures, and rules of scientific classification and the naming of organisms
(Science of classifying organisms)
Phylogenetics
What cladistics is sometimes referred to because cladograms are generated from similarities in the molecular structure of organisms
Theory of evolution
postulates that the modern species of organisms are descendants of a common ancestor and that their present characteristics have come from genetic variation and natural selection
Species
Members of a species share common genes and can breed to produce fertile offspring
Fossil
A preserved remnant or impression of an organism
Fossil record
the sequence of fossils from the oldest to the most recent
Homologous structures
Structures who’s similarity is due to descent from a common ancestor
Divergent evolution
What homologous structures result from as related organisms expand into new environments
Analogous structures
Have similar functions in unrelated organisms (ex: butterfly and bat wings)