Genetic Variation, Evolution, and Protists Vocabulary

Flashcards about genetic variation and evolution, agents of evolutionary change, protists, and endosymbiosis.

Genetic Variation

The different alleles of genes found within individuals of a population.

Evolution

How an entity (social system, gas, or planet) changes through time, or descent with modification where species accumulate differences over time.

Genetic Variation

The different alleles of genes found within individuals of a population.

Evolution

How an entity (social system, gas, or planet) changes through time, or descent with modification where species accumulate differences over time.

Population Genetics

The study of genetic variation within populations.

Morphological Variation

Obvious differences in physical traits that often result from underlying genetic differences in a population.

Single-Nucleotide Polymorphisms (SNPs)

Single-base differences between individuals that exist in the population at more than 1%.

Mutation

Change from one allele to another; the ultimate source of genetic variation.

Gene Flow

The movement of alleles from one population to another.

Nonrandom Mating

Individuals with certain genotypes mate with one another more commonly than would be expected on a random basis.

Assortative Mating

Phenotypically similar individuals mate, increasing the proportion of homozygotes.

Inbreeding

Closely related individuals mate with each other, increasing the proportion of homozygotes.

Disassortative Mating

Phenotypically different individuals mate, producing an excess of heterozygotes.

Genetic Drift

Changes in allele frequencies occur randomly, particularly in small populations.

Founder Effect

Allele frequencies of founding individuals are different from the allele frequencies in the population from which they came.

Bottleneck Effect

Population size is drastically reduced, resulting in altered allele frequencies and loss of genetic variability.

Selection

Individuals with one phenotype leave more surviving offspring than individuals with an alternative phenotype.

Fitness

Reproductive success; the number of surviving offspring left in the next generation.

Sexual Selection

Selection with respect to mating success.

Endosymbiosis

A critical stage in the evolution of eukaryotic cells involved endosymbiotic relationships with prokaryotic organisms.

Eukaryotes

From the Greek words meaning "true nucleus," because they possess an internal structure called a nucleus.

Protists

A paraphyletic group of eukaryotes that are not classified as animals, plants, or fungi.

Endosymbiotic Bacteria

Bacteria that live within other cells and provide some benefit for their host cells.

Mitosis

The systematic separation of chromosomes during cell division.

Cyst

A dormant form of a cell with a resistant outer covering that some protists can form to survive and reproduce asexually in harsh conditions.

Meiosis

A major evolutionary innovation that arose in ancestral protists and allows for the production of haploid cells from diploid cells and the generation of genetic diversity.