epitoke
Quick Summary
The term "epitoke" refers to the posterior, sexually mature part of certain polychaete worms that develops from the anterior, sexless portion. These epitokes are reproductive forms that, at specific times of the year, swarm to the ocean's surface to release eggs and sperm. This process is crucial for sexual reproduction in many marine worms, with some species exhibiting behaviors like chemical attraction or bioluminescence to facilitate mating. The epitoke is a biological adaptation for reproduction in these segmented worms.12
It is important to distinguish this from "epitaxy," which is a materials science process involving growing a crystal layer on top of another crystal, with the orientation determined by the underlying crystal.3
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palolo worm…the tail section (the “epitoke”), bearing reproductive cells, swims to the surface, where it releases eggs and sperm. Tens of thousands of epitokes swarm and release gametes simultaneously, attracting predatory fish and humans. The front section of the worm (the “atoke”) remains below in the substrate.
Read More…the tail section (the “epitoke”), bearing reproductive cells, swims to the surface, where it releases eggs and sperm. Tens of thousands of epitokes swarm and release gametes simultaneously, attracting predatory fish and humans. The front section of the worm (the “atoke”) remains below in the substrate.
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annelidReproduction…the two most profound being epitoky (maturation into a modified, fertile form) and stolonization (the development of stemlike growths). In species of Nereis, morphological changes include enlargement of the eyes, enlargement of a specific number of parapodia, replacement and alteration of setae, and development of an anal organ (rosette) for…
Read More…the two most profound being epitoky (maturation into a modified, fertile form) and stolonization (the development of stemlike growths). In species of Nereis, morphological changes include enlargement of the eyes, enlargement of a specific number of parapodia, replacement and alteration of setae, and development of an anal organ (rosette) for…
Read More- reproductive behaviourSegmented worms
…produce a reproductive form (epitoke). At a certain time of the year, the epitokes swarm to the ocean surface and engage in mass shedding of eggs and sperm. Some female epitokes of clam worms (Nereis) produce a chemical substance called fertilizin that attracts the male epitokes and stimulates the…
Read More…produce a reproductive form (epitoke). At a certain time of the year, the epitokes swarm to the ocean surface and engage in mass shedding of eggs and sperm. Some female epitokes of clam worms (Nereis) produce a chemical substance called fertilizin that attracts the male epitokes and stimulates the…
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