Endoreduplication

Part of speech: noun

Definitions

1. A biological mechanism characterized by the duplication of a cell's genome, which results in an increased number of chromosomes without typical mitosis
2. A phenomenon in cellular biology where replication of the genetic material occurs multiple times, causing polyploidy and enhanced chromosomal content in one cell
3. A process in cell biology where the genetic material is duplicated within a single nucleus, leading to an increase in chromosome number without undergoing the conventional cell division process

Etymology: Endoreduplication is a compound built from two parts. The first, "endo-", comes from Greek "endon", meaning "within", and is used in English to mark something happening inside a structure or body. The second part, "reduplication", refers to the act of copying or doubling. Put together, the term describes a cell that copies its genetic material again and again without dividing into two cells afterwards. The result is a cell that grows steadily richer in chromosomes. Each round of copying adds another set, so the nucleus ends up with many times the normal amount of genetic material, a state known as polyploidy. Because the copying happens inside a single cell, the cell itself becomes larger and more heavily loaded, rather than splitting to produce new cells. The word is a transparent coinage from modern biology, so its parts explain nearly all of its meaning: the "endo-" tells you the doubling stays inside, and "reduplication" tells you what is being doubled.