Chp 4, Forces of Evolution Flashcards
What is a Deme?
Local population of organisms that have similar genes, interbreed, and produce offspring
What is a Gene pool?
All the genetic information in the breeding population
What is Reproductive Isolation?
If 2 populations are reproductively isolated, then members of the 1 population cannot interbreed with members of another
What is a Species?
Population that produce viable offspring
What is a Microevolution?
Small-scale evolution i.e change in allele frequency from 1 generation to another
What is a Macroevolution?
Large-scale evolution i.e. speciation event that occurs after 100 or 1,000 of generations
What is Equilibrium?
Conditions in which the system is stable, balanced, and unchanging
What is Population genetics?
Study of changes in genetic material➡️ the change in frequency of genes
Who is Anthony Allison?
Popularized the theory of population genetics➡️ gene frequency is tied to natural selection
What is the Harvey-Weinberg law?
Mathematical model in population genetics that shows relations between frequencies of alleles & genotypes can be used to determine whether a population is going through evolutionary change
Genetic change is a result from____?
Mutation, Gene drift, Gene flow, Natural selection
What is a Mutation?
Any heritable change in the structure of genetic material➡️ absence of gene flow only source of new genetic variation w/in a population➡️ noncoding DNA doesn’t affect one’s survival, but coding may have consequences
What is Point mutation?
Replacements of a single nitrogen base with another, may or may not affect the amino acid of triplet codes
What is Synonymous mutation?
Neutral point mutation substituted nitrogen bases create a triplet coded to produce the same amino acids as original triplet
What is a Nonsynonymous mutation?
Point mutation that creates a triplet coded to produce a different amino acid from that of the original triplet i.e sickle-cell anemia
What is Frameshift?
Change in a gene➡️ insertion or deletion of 1 or more nitrogen bases➡️ triplets will rearrange & codons will be read wrong during translation
What are Transposable elements?
Mobile pieces of DNA that can copy itself into entirely new areas of the chromosomes
What is Klinefelter’s syndrome
Chromosomal trisomy➡️ males have extra X chromosomes
What is Spontaneous mutation?
Random changes in DNA that occur in cell division
What is Induced mutation?
Resulting from exposure to chemical toxins or radiation usually from human activity
What are Mutagens?
Toxins, etc that may induce genetic mutations
What is Fitness?
The average number of offspring by parents with a particular genotype compared to the number of offspring by parents with another genotype
What is Natural selection?
Individuals with advantageous traits will survive in higher numbers and produce more offspring
What is Direct selection?
Selection for 1 allele over the other➡️ shift in 1 direction
What is Stabilizing selection?
Selection against extrems of the phenotypic distributions ➡️ decreasing genetic diversity of this trait for population
What is Disruptive selection?
Selection for both extremes of the phenotype distributions➡️ may lead to a speciation event
What is Melanic?
High concentration of melanin
What is Positive selection?
Process in which beneficial genetic variations quickly increase in frequency in a population
What is Sickle-cell anemia?
Genetic blood disease➡️ red blood cells become sickly➡️decreasing their ability to carry oxygen to tissues
What is Hemolytic anemia?
Conditions of insufficient iron in the blood➡️ destruction of red blood cells b/c of genetic blood diseases
What is Abnormal hemoglobin?
Hemoglobin altered ➡️ less efficient in binding carrying oxygen
What are Capillaries?
Narrow blood vessels that from network via the tissues
What are Balanced polymorphisms?
Selection maintains 2 or more phenotypes for a specific gene in a population
What is Anthropogenic?
Any effect caused by humans
What is Thalassemia?
Genetic blood disease➡️hemoglobin is improperly synthesized causing the red bl. Cells have a shorter lifespan
What is G6PD?
Enzyme that aids in the paper functioning of red blood cells; its deficiency, a genetic condition➡️ hemolytic anemia
What is Endogamous?
Pop. In which individuals breed only with other members of the pop.
What is Exogamous?
Pop. In which individuals breed with nonmembers of their pop.
What is the Founder effect?
Form of genetic drift➡️ small group of a large parent pop. Migrates to a new region that is reproductively isolated
What is Huntington’s chorea?
➡️ Rare genetic disease caused by an autosomal dominant gene➡️symptoms often appearing btwn ages 30 & 50
What is Admixture?
Exchange of genetic material btw. 2 or more pop.
What is Demic diffusion?
Pop. Movement into an area previously uninhabited by that group
What is Homology ?
Similarities between organisms based on descent from a common ancestor
What is Homoplasy?
a shared character between two or more animals that did not arise from a common ancestor
What is Anagenesis?
the progressive evolutionary changes that take place over time in a single genetic lineage without branching off, gradual evolution
What is Cladogenesis?
in which a lineage splits into two or more separate lines
