ap·op·to·sis (ăp′əp-tōsĭs, ăp′ə-tō-)
A natural process of self-destruction by degradative enzymes in certain cells, such as epithelial cells and erythrocytes, that are genetically programmed to have a limited lifespan or are damaged, as by irradiation or toxic drugs. Also called programmed cell death.
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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