Bacteria took sea grass (which is not a usable food for many organisms) and not only turned it into a form of food that was usable but also enriched the food. Please explain.
(*I'm thinking that the sea-grass isn't usable because it's probably a form of cellulose and then I"m thinking that they nitrogen cycle somehow helps convert but I can't completely explain.)
You are correct in your reasoning. Seagrass does in fact contain a lot of cellulose. There are some fish that can consume seagrass but only because they have symbiotic relationships with bacteria that break down ...
Explanation and web links regarding the use of sea grass as an enriched food source.