MICRONUCLEUS Meaning and
Definition
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A micronucleus is a small and distinct nucleus present in certain cells, such as the cells of protozoans or certain animal and plant cells. It is often seen as an additional nucleus and is typically smaller than the main nucleus found in the same cell. The micronucleus can be spherical or ellipsoidal in shape, varying based on the species and cell type.
In protozoans, the micronucleus plays a vital role in reproduction. During sexual reproduction, the micronucleus undergoes meiosis, resulting in haploid micronuclei. These micronuclei are then exchanged between mating partners, allowing genetic diversity and recombination to occur.
For certain animal and plant cells, the micronucleus can be formed through a variety of processes, such as fragmentation or budding off from the main nucleus. It serves as an additional reservoir of genetic material or acts as a backup for essential genes. The micronucleus may also contribute to genomic stability and repair during cell division or in response to genotoxic stress.
The study and observation of micronuclei can provide valuable insights into various areas of research, including genetic variation, reproductive biology, and cellular responses to environmental stressors or disease. Micronucleus analysis has become a common technique in genotoxicity studies, helping detect and measure DNA damage or chromosomal abnormalities, as micronuclei often appear when a cell's DNA is damaged or when chromosome rearrangements occur.
Overall, micronucleus refers to a small and distinct nucleus found in certain cells, serving important functions in reproduction, genetic stability, and cellular response to external factors.
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1. A small nucleus in a large cell. 2. Specifically, the smaller of the two nuclei in infusoria, dividing mitotically, containing the specific inheritable germ substance; germ nucleus, gonad nucleus, caryogonad. See macronucleus.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
Etymology of MICRONUCLEUS
The word "micronucleus" is derived from the combination of two Greek words: "mikros" meaning "small" and "nucleus" referring to the central part of a cell.
In biology, a micronucleus refers to a small, secondary nucleus found within some eukaryotic cells, such as protozoans and some cells in certain animals and plants.
Similar spelling words for MICRONUCLEUS
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