Bio Week 3 Evolutionary principles

5 Core Concepts of Biology

Evolution, Structure and function, information flow exchange and storage, pathways and transformations of energy and matter, and systems

Evolution

A heritable change in a population of organisms from one generation to the next.

Biological evolution

A heritable change in one or more characteristics in a population of organisms from one generation to the next.

Heritable

(1) A trait that can be transmitted from parent to offspring. (2) A property of DNA, which means that it can be passed from cell to cell and from parent to offspring.

Mutation

A heritable change in the genetic material.

Lineage

A series of species that forms a line of descent.

Vertical Evolution

A type of evolution in which genetic changes occur in a series of related species that form a lineage; species evolve from pre-existing species by the accumulation of genetic changes.

Horizontal Gene Transfer

A process in which an organism incorporates genetic material from another organism without being the offspring of that organism.

Genome/ Proteome

The complete genetic material of an organism or species.

Genotype/ Phenotype

The genetic composition of an individual

Taxonomy

The field of biology that is concerned with the theory, practice, and rules of classifying living and extinct species and also viruses.

Binomial Nomenclature

The standard format for scientific names of species. Each species has a genus name and a specific epithet.

Prebiotic soup

The medium formed by the slow accumulation of organic molecules in the early oceans over a long period of time prior to the existence of life.

Organic Molecules

A carbon-containing molecule, so named because such molecules were first discovered in living organisms.

Protobiont

the term used to describe the first nonliving structure that could have evolved into a living cell.

RNA world

A hypothetical period on primitive Earth when both the information needed for life and the catalytic activity of living cells were contained solely in RNA molecules.

Chemical Evolution

The process by which a population of molecules changes over time to become a new population with a different chemical composition.

Microevolution

Changes in a population’s gene pool, such as changes in allele frequencies, from generation to generation.

Macro evolution

Evolutionary changes that produce new species or groups of species.

Species

In taxonomy, a subdivision of a genus. Each species is a group of related organisms that share a distinctive set of attributes in nature and (for sexually reproducing species) are capable of interbreeding.

Population

A group of individuals of the same species that occupy the same environment and (for sexually reproducing organisms) can interbreed with one another.

Molecular evolution

The process of evolution at the level of genes and proteins.

Inheritance of acquired characteristics ( Lamarckian Evolution)

Natural selection

The process that eliminates those individuals that are less likely to survive and reproduce in a particular environment, while allowing other individuals with traits that confer greater reproductive success to increase in numbers.

Trait

An identifiable characteristic; usually refers to a variant.

reproductive success

The likelihood that an individual will contribute fertile offspring to the next generation.

adaptation

Changes in populations of living organisms that are the result of natural selection and that increase their ability to survive and reproduce in their environment.

Artificial selection/ selective breeding

Programs and procedures designed to modify traits in domesticated species.

Allele

A variant form of a gene.

Convergent Evolution

The process whereby two species from different lineages independently develop similar characteristics because they occupy similar environments.

Analogy (analogous structure)

A structure that is the result of convergent evolution. Such structures have arisen independently, two or more times, because species have occupied similar types of environments on Earth.

Fossil

Recognizable preserved remains of past life on Earth.

Transitional forms

An organism that provides a link between earlier and later forms in evolution.

Homology

A similarity that occurs due to descent from a common ancestor.

Vestigial structures

An anatomical feature whose function is reduced or absent but that resembles a structure of a presumed ancestor.

Paralog/Ortholog

Homologous genes within a single species.

Genetic variation

Genetic drift

The random change in a population’s allele frequencies from one generation to the next that is attributable to chance. It occurs more quickly in small populations.

Gene Flow/ migration

A transfer of alleles into or out of a population that occurs when fertile individuals migrate between populations having different allele frequencies.

Nonrandom Mating

The phenomenon that occurs when individuals choose their mates based on their genotypes or phenotypes.