replications

Replications refer to processes involving duplication or reproduction. In science, replication means repeating a study or experiment to determine whether its findings hold under similar conditions. In biology, replication specifically describes the copying of genetic material before cell division. The term thus covers both methodological verification and a fundamental cellular mechanism.

In scientific research, replication can be direct, where the study closely mirrors the original methods and conditions, or conceptual, where the same hypothesis is tested with different methods or data. Researchers may also perform independent replication or include replicates to estimate variability and precision.

Replicability and reproducibility are related but distinct concepts. Replicability generally means obtaining consistent results in new studies that test the same question with new data and samples; reproducibility often refers to reanalyzing the original data or code to reach the same conclusion.

A replication crisis has emerged in several fields, with many effects failing to replicate. Contributing factors include small samples, p-hacking, selective reporting, and publication bias. Responses include preregistration, data and code sharing, registered reports, larger multi-site studies, and explicit incentives to publish replication results.

In biology, DNA replication is the process by which a cell copies its genome before division. It is semi-conservative, starting at origins of replication with replication forks. Enzymes such as helicase, primase, DNA polymerase, and ligase coordinate primer synthesis, strand synthesis, and joining, with proofreading to maintain fidelity.