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Showing 1–30 of 241 reference entries

BiologyCells as units of life

Cell theory describes the organization and reproduction of cellular life.

ModelBiologyDNA and sequence information

DNA's base sequence stores biological information.

DefinitionBiologyGene expression

Gene expression produces functional RNA or protein from gene information.

DefinitionBiologyDNA replication

Complementary base pairing allows DNA strands to serve as copying templates.

ModelBiologyCell cycle, mitosis and cytokinesis

DNA duplication, nuclear division and cytoplasmic division are distinct events in a typical mitotic cycle.

ModelBiologyMeiosis and chromosome segregation

Typical diploid meiosis halves the number of chromosome sets through two divisions after one DNA replication.

ModelBiologyAlleles and Mendelian segregation

A diploid individual's paired alleles can segregate into gametes.

ModelBiologyBiological evolution

Evolution concerns inherited change across generations.

DefinitionBiologyNatural selection

Heritable variation can change through differences in reproductive contribution.

ModelBiologyGenetic drift

Chance can change allele frequencies independently of an adaptive advantage.

ModelBiologyCommon ancestry and branching lineages

Evolutionary relationships describe descent from shared ancestors.

ModelBiology · ChemistryMetabolism and chemical pathways

Metabolism comprises the regulated chemical reactions of living systems.

DefinitionBiologyOxygenic photosynthesis

Oxygenic photosynthesis couples light-energy capture to carbon fixation and releases oxygen from water.

ModelBiologyAerobic cellular respiration

Aerobic respiration couples nutrient oxidation to ATP production, using oxygen as the final electron acceptor.

ModelBiologyMembranes and transport

Selective membranes and transport proteins regulate movement between a cell and its surroundings.

ModelBiologyEcology and ecosystems

Ecology examines organisms' interactions with one another and their physical environment.

DefinitionBiologyHomeostasis and negative feedback

Feedback can maintain internal variables within functional ranges.

ModelEarth & cosmos · Biology · ChemistryEarth's carbon cycle

Carbon moves through biological, oceanic, atmospheric and geological reservoirs.

ModelBiologyMajor biomolecule classes

Carbohydrates, lipids, proteins and nucleic acids organize much of cell chemistry.

DefinitionBiologyProtein structure and molecular function

Sequence, folding and assembly provide different levels of protein description.

ModelBiologyMichaelis–Menten enzyme kinetics

A simple enzyme–substrate mechanism predicts saturating initial rates.

ModelBiologyATP hydrolysis and energy coupling

Coupled reaction pathways connect favourable chemistry with cellular work.

ModelBiologyMutation and sequence variation

Mutation changes DNA sequence and can introduce inherited variation.

DefinitionBiologyGene flow between populations

Movement contributes to gene flow when genetic material enters a population's reproduction.

ModelBiologyExtensions to simple Mendelian inheritance

Allele segregation and phenotype dominance are different questions.

ModelBiologyTranscriptional regulation

DNA-binding regulators and cellular signals affect transcription.

ModelBiologyEpigenetic marks and gene regulation

DNA-associated marks can affect expression without changing DNA sequence.

ModelBiologySpecies concepts and their limits

Species boundaries depend on the organisms and the question being investigated.

DefinitionBiologySpeciation and reproductive isolation

Reduced reproductive exchange can permit populations to diverge into lineages.

ModelBiologyPhylogenetic inference from characters

Evolutionary trees are hypotheses inferred from comparative evidence.

Method
DefinitionSource checked

Biological evolution

Biology

Evolution concerns inherited change across generations.

Key knowledge

Biological evolution is descent with inherited modification. At the population level, a change in allele frequencies across generations is one way to describe evolutionary change; an individual's growth or temporary acclimation is not, by itself, such a change.

Conditions and scope

  • Specify the population, inherited feature and generations being compared.
  • Evolution does not mean inevitable progress toward greater complexity or a predetermined goal.
Sources · 5

References

Sources retain their recorded scope. A source link alone does not establish verification of every statement.

  1. University of California Museum of Paleontology, Berkeley2 sources
    1. Understanding Evolution: An introduction to evolutionUniversity of California Museum of Paleontology, BerkeleyTeaching resourceevolution.berkeley.eduRead source
    2. Understanding Evolution: the family treeUniversity of California Museum of Paleontology, BerkeleyReference guideevolution.berkeley.eduRead source
  2. Mary Ann Clark, Matthew Douglas and Jung Choi — OpenStax, Rice University2 sources
    1. Biology 2e, 19.1 Population EvolutionMary Ann Clark, Matthew Douglas and Jung Choi — OpenStax, Rice UniversityTextbook chapteropenstax.orgRead source
    2. Biology 2e, 19.3: Adaptive EvolutionMary Ann Clark, Matthew Douglas and Jung Choi — OpenStax, Rice UniversityTextbook chapteropenstax.orgRead source
  3. Biology XII: EvolutionNCERTTextbook chapter · PDFncert.nic.inRead source

Evidence and review

Published distinction between inherited population change and individual change; no allele-frequency dataset was newly analysed.

2026-10-10 · English definition checked against UCMP's introduction and population-genetic account; a complete theory of every evolutionary process is not claimed.

Foundational review

2026-10-10 · Fresh primary-source inspection of the complete compact record, including every statement, equation, quantity and material condition, followed by independent AI editorial review. This check does not certify all linked lessons or every passage of every cited publication.

Sources from other places

Agreement within this scope

Inherited branching change and population allele-frequency change.

Evolution is not an individual’s temporary acclimation.

  • NCERT

    • Biology XII: Evolution
      IndiaEnglish

      §6.3, printed pp113–115: homology and common ancestry; §6.5, printed p118: branching descent and heritable fitness; §6.7, printed pp120–121: allele-frequency changes and chance drift

Related reference entries

Explore relationships within this area of study and its connections to other areas.

Showing 1–6 of 6 relationships

Scientific relationships · 6 / 6

The relationship type describes the connection. Its linked statements, sources and conditions define the scope.

  1. Related to
    Relationship sources · 1

    Linked statements

    • In ordinary Mendelian segregation, the two alleles at a locus in a diploid individual separate during gamete formation, so each gamete receives one of them. Fertilization combines parental alleles. This discrete inheritance differs from permanent blending of parental hereditary factors.
    • Biological evolution is descent with inherited modification. At the population level, a change in allele frequencies across generations is one way to describe evolutionary change; an individual's growth or temporary acclimation is not, by itself, such a change.

    Population genetics connects inherited alleles with changes in their frequencies.

  2. Related to
    Relationship sources · 2

    Linked statements

    • Natural selection occurs when heritable differences affect organisms' contributions to later generations. Variants associated with greater reproductive contribution in the relevant environment can become more frequent, producing adaptation under suitable conditions.
    • Biological evolution is descent with inherited modification. At the population level, a change in allele frequencies across generations is one way to describe evolutionary change; an individual's growth or temporary acclimation is not, by itself, such a change.

    Selection is one mechanism that can change inherited population composition.

  3. Related to
    Relationship sources · 1

    Linked statements

    • Genetic drift is random change in allele frequencies due to chance in which genetic variants are transmitted to later generations. It can cause a variant to be lost or fixed without that outcome being caused by a reproductive advantage of the variant.
    • Biological evolution is descent with inherited modification. At the population level, a change in allele frequencies across generations is one way to describe evolutionary change; an individual's growth or temporary acclimation is not, by itself, such a change.

    Chance transmission is an evolutionary mechanism, not an adaptive advantage.

  4. Related to
    Relationship sources · 2

    Linked statements

    • Different species can descend from a shared ancestral lineage. Evolutionary trees represent these branching relationships and the inheritance of features from common ancestors, rather than a ladder ranking present-day species.
    • Biological evolution is descent with inherited modification. At the population level, a change in allele frequencies across generations is one way to describe evolutionary change; an individual's growth or temporary acclimation is not, by itself, such a change.

    Descent with modification connects lineage change with shared ancestors.

  5. Related to
    Relationship sources · 1

    Linked statements

    • Gene flow transfers genetic variants among populations through reproductive contribution of migrants or transferred genetic material, such as pollen. It can alter allele frequencies and connect populations that would otherwise evolve separately.

    Genetic contributions between populations can change variant frequencies.

  6. Related to
    Relationship sources · 2

    Linked statements

    • The Phanerozoic comprises the Paleozoic, Mesozoic and Cenozoic eras. The Paleozoic records major marine animal diversification and progressive colonization of land. Mesozoic terrestrial records include dinosaur diversification and Cretaceous flowering-plant expansion. Cenozoic records show diversification of surviving lineages, including mammals, across substantial climatic and environmental changes.

    Descent and evolutionary change connect organisms across geological time.

Entry detailsPermanent link to this entry ↗
Record identity
bio-evolution
Revision
core.1
Structured reference record
Essential core · first collection