These &quot;primary producers,&quot; i.e. algae and some bacteria, exist at the lowest levels of the food chain and use sunlight or chemical energy, rather than other organic material, as sources of energy.
(These &quot;primary producers,&quot; i.e. algae and some bacteria; exist; L:at the lowest levels of the food chain)
These &quot;primary producers,&quot
i.e. algae and some bacteria
exist L:at the lowest levels of the food chain