In cell biology, an organelle is a discrete structure of a cell having specialized functions. There are many types of organelles, particularly in the eukaryotic cells of higher organisms. An organelle is to the cell what an organ is to the body (hence the name organelle, the suffix -elle being a diminutive). Organelles were historically identified through the use of microscopy, and were also identified through the use of cell fractionation.
A few large organelles probably originated from endosymbiont bacteria:
Plant :: Eukaryotic
Prokaryotic :: Genetics

Mitochondrial DNA Concordance - Features a cross-referenced list of single nucleotide substitutions in the two hypervariable segments of the mtDNA control region.
MitoDat - This database is dedicated to the nuclear genes specifying the enzymes, structural proteins, and other proteins, many still not identified, involved in mitochondrial biogenesis and function.
MITOMAP - Genome database of polymorphisms and mutations of the human mitochondrial DNA .
The Kennell Lab - Saint Louis University - Mitochondrial research, especially the genetics of filamentous fungi. Includes information describing mitochondrial genomes, mutants, extrachromosomal plasmids, and nuclear genes involved in mitochondrial function.
| Biology IX - Cell Organelles | |
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