Nembrotha kubaryana photographed with fluorescence filters.

Collecting nudibranchs at Lizard Island.

PAM measurements in variable light conditions.

Photosynthesis in opisthobranchia

Solar panels (photosynthesis) is not a process exclusivly found in higher plants and algae, but is a potentially widespread process in marine invertebrates. Sacoglossans (gastropoda, opisthobranchia) like Elysia viridis and Placida (Hermaea) dendritica in the Trondheim fjord are herbivores feeding on the cell sap of green algae. They ingest whole chloroplasts, and have the potential of utilising photosynthetically functional chloroplasts.

This project is funded by the Norwegian Research Council, and is done with the supervision and collaboration of professor Geir Johnsen (TBS, NTNU). The main aim is to identify and quantify the photosynthetic processes and performance in the symbiotic organelles (chloroplasts) found in sacoglossan opisthobranchs.

By using Pulse Amplitude Modulated Fluorometry it is possible to detect the presence of photosynthetically active chloroplasts in sacoglossa in situ. Lab experiments using the same method also allows us to investigate the fluorescence kinetics in photosystem II, the rate of photosynthesis and light utilisation.

Time series measurements of key environmental variables as irradiance (surface and under water), temperature and salinity are compared with possible variation in pigment composition in the sacoglossans.

This project also collaborates with Ingo Burghardt and professor Heike Wägele (Ruhr Universität, Bochum) who are studying zooxhanthellae in nudibranchs.

This document maintained by jussi.evertsen(a)bio.ntnu.no
Last updated 3 November 2004