Mitochondria are known as the powerhouses of the cell. The energy required for various chemical activities needed for life is released by mitochondria in the form of ATP ( Andenosine Triphopshate) molecules. The body uses energy stored in ATP for making new chemical compounds and for mechanical work. Mitochondria have two membrane coverings instead of just one. Mitochondria are strange organelles in the sense that they have their own DNA and ribosomes.