Quiz Nov. 12 Flashcards
(29 cards)
What is Genetic Drift? Describe the two mechanisms.
Genetic Drift: A random change in allele frequency
Bottleneck Effect: a change in allele frequency following a dramatic reduction of population
Founder Effect: Change in allele frequency as a result of a small group migrating
What is the basis of genetic variation?
Lateral Gene Transfer: Bacteria swap traits between individuals and species
Genetic Recombination: meiosis and crossing-over during sexual reproduction
Mutation: a random change in genetic data
Fitness
describes how well an organism can survive an reproduce in its environment
Adaptation
an organism’s ability to survive and reproduce in its environment
Natural Selection
Process by which organisms with variations most suited to their local environment survive and leave more offspring
What are the requirements for Natural Selection to occur?
1) the struggle for existence - more individuals are born that can survive
2) Variation and Adaptation - heritable, advantageous traits
3) Survival of the Fittest - fitness among individuals
Taxonomy
method of classifying organisms
Binomial Nomenclature
classification system in which each species is assigned two-part scientific name
Cladogram
a diagram depicting patterns of shared characteristics among species
Clade
a common ancestor and all of its descendents
Phylogeny
the study of evolutionary relationships that exist between species
Molecular Phylogeny
Phylogeny in therms of genetic data
Species
population or group of populations whose members can interbreed and produce fertile offspring
Speciation
a process by which new species are formed
What is reproductive isolation? What are the different mechanisms of reproductive isolation?
Reproductive Isolation: separation of a species or a population so that they can no longer interbreed; evolve two separate species
Behavioral: different behaviors (courtship rituals) that prevent breeding
Geographic: separated by geographic location
Temporal: reproduce at different times
Adaptive Radiation
a small population evolves into many different forms
Vestigial Structures
inherited from ancestors but have lost much or all of their function
Analogous Structures
body parts that share common function
Homologous Structures
structures that are shared by a related species and have inherited from a common ancestor
Common Ancestor
two species that evolved from the same species long ago; separated because of derived characters
Genotype
genetic makeup of an organism
Phenotype
physical traits or characteristics of an organism
Allele
one of a number of different forms of a gene
Frequency
occurrence percentage in a population
