Biology natural selection

Paradigm shift

Change in scientific understanding contradicting previous beliefs.

Natural selection

Process where organisms better adapted survive and reproduce.

Mutation

Change in DNA creating new alleles.

Meiosis

Cell division producing genetic variation in offspring. Produces 4 haploid daughter cells

Sexual reproduction

Combines genes from two parents, increasing variation.

Asexual reproduction

Single parent reproduction, limited variation.

Intraspecific competition

Competition among individuals of the same species.

Abiotic factors

Non-living environmental factors affecting organisms.

Density-independent factors

Environmental pressures not influenced by population density.

Density-dependent factors

Environmental pressures influenced by population density.

Fitness

Heritable traits enhancing survival and reproduction.

Evolutionary change

Cumulative alteration in allele frequencies over time.

Acquired traits

Characteristics gained during life, not inherited.

Sexual selection

Mate choice based on advantageous traits.

Gene pool

Total genetic diversity within a population.

Neo-Darwinism

Integration of natural selection and genetics.

Allele frequency

Proportion of a specific allele in a population.

Stabilising selection

Average phenotypes favored over extremes.

Disruptive selection

Extreme phenotypes favored over average ones.

Directional selection

One extreme phenotype favored over another.

Hardy-Weinberg equation

p² + 2pq + q² = 1

Artificial selection

Human-directed breeding for desired traits.