Storing sperm and Egg cells to later create babies when desired.
Parents controlling the baby sex that is produced.
Hypothesis and conclusion
Organelle,
Cells,
Tissues,
Organs,
Organ System,
Organisms,
Populations,
Communities,
Ecosystems,
And Biosphere
The same principle apply to stereo microscopes, a 10X eye piece combined with a 4X objective lens will produce 40X magnification.