Current thinking on how the Toxoplasma gondii parasite invades its host is incorrect, according to a study published today in Nature Methods describing a new technique to knock out genes. The findings could have implications ...
Definition. Coral bleaching is a process whereby the coral colonies lose their colour, either due to the loss of pigments by microscopic algae (zooxanthellae) living in symbiosis with their host organisms (polyps), or because these zooxanthellae have been expelled.
Bleaching is a stress response that results when the coral-. algae relationship breaks down. The term 'bleaching'. describes the loss of colour that results when zooxanthellae. are expelled from the coral hosts or when pigments within. the algae are degraded.