endogenous
adjective
Did you know?
When biologists need to make a distinction between things that are produced within a cell or organ and things that affect it from the outside, they use the terms endogenous and exogenous. It used to be thought, for instance, that mutations in cells always resulted from exogenous causes, until it was discovered that substances in the body, including those called oxidants, could cause them endogenously as well. "Circadian rhythms"—the regular cycles, roughly 24 hours in length, that plants, animals, and humans rely on to regulate their days—are endogenously generated and don't actually depend on the sun for their timing.
Examples of endogenous in a Sentence
Maia Szalavitz, Scientific American, 17 Sep. 2024
And during scary or stressful experiences, endogenous, or self-generated, opioids known as endorphins and enkephalins are released in the brain.
—Maia Szalavitz, Scientific American, 17 Sep. 2024
There are two primary types of Cushing syndrome: exogenous and endogenous, which are differentiated based on the cause of the disorder.
—Madeline Nguyen, The Arizona Republic, 12 June 2024
In addition to being the active ingredient in ayahuasca, DMT is an endogenous molecule synthesized naturally in mammalian brains.
—Jon Brodkin, Ars Technica, 2 Oct. 2023
See all Example Sentences for endogenous 
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'endogenous.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Dictionary Entries Near endogenous
Cite this Entry
“Endogenous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/endogenous. Accessed 5 Nov. 2024.
Copy CitationMedical Definition
endogenous
adjective
Share