What organ is like the mitochondrion besides the stomach?

only about ten percent of the energy at one trophic level is passed on to organisms at the next trophic level. the remainder of the energy is used in life processes or lost as heat.

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.

yes, because even though a theory has a  lot of evidence to support it, it is not always true