What is the source of energy for organisms that use chemosynthesis

What claim did thorne make? what evidence supported his claim?

Consider an organism that is eukaryotic, found in both unicellular and multicellular forms, may resemble a plant but is not photosynthetic, has chitin in its cell walls, and absorbs organic nutrients from decomposing material in the environment. this organism would be classified as which of the following types of organisms? a. fungib. protozoac. bacteriad. archaea

What is thought to have caused the mass extinction at the end of the cretaceous period?