surface area inside the mitochondria
"The surface area inside the mitochondria is like the table top where the reactions to break down food can take place. The more tabletop space you have, the more energy you can create. All around inside the mitochondria is a fluid called MATRIX."
The link contains a pretty good explanation for most parts of the mammalian cell.
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.