DNA is a molecule that contains the genetic instructions used in the development and functioning of all living organisms.
Sexual reproduction involves the fusion of two gametes, typically from different individuals, to produce offspring with genetic diversity.
A gene is a segment of DNA that contains the instructions for a particular trait or function.
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product, such as a protein.
Noncoding DNA refers to segments of DNA that do not contain the instructions for making proteins, but may still play a role in gene regulation and other cellular processes.