Complexity in free-living eukaryotic cells. (a) The giant ciliate Stentor coeruleus, a classic system for studying cellular pattern formation using microsurgical methods . Each cell can be up to 2 mm long and has a complex and highly asymmetrical morphology that can be faithfully regenerated following surgical manipulation. Image courtesy of Biodiversity Heritage Library. http://www.biodiversitylibrary.org webcite. (b) Ventral surface of Stylonychia  showing distinct classes of cirri arranged in highly asymmetrical patterns that are reproducible from cell to cell. Reprinted from Developmental Biology  with permission from Elsevier. (c) Apical complex (from which the apicomplexans take their name) of Toxoplasma cell  containing distinct sets of microtubule-based structures. (d) Basal apparatus of Chlamydomonas  showing the complex inter-relationship between the two mature basal bodies, the two daughter basal bodies formed prior to division, four microtubule-based rootlets, and several accessory fibers linking the rootlets to the basal bodies. These complex geometrical relations surrounding centrioles and basal bodies are likely a key source of local positional information. Reproduced with permission from Journal of Cell Science .
Marshall BMC Biology 2011 9:57 doi:10.1186/1741-7007-9-57