Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

The mitochondria organelles are known as the "power plants" of the cell.
What organelles are known as the "power plants" of the cell?

The reverse process of moving material into a cell is the process of exocytosis.
The reverse process of moving material into a cell is the process of what?

Bones are made up of different types of tissue.

Bones are made up of different types of what?