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

[Q]: All cells have the small size in common.
[A]: What do all cells have in common?


[Q]: Ecological pyramids can demonstrate the decrease in energy, biomass or numbers within an ecosystem.
[A]: What can demonstrate the decrease in energy, biomass or numbers within an ecosystem?


[Q]: When oxygen is not bound to heme and the partial pressure of oxygen is low, hemoglobin readily binds to carbon dioxide.
[A]:
When oxygen is not bound to heme and the partial pressure of oxygen is low, hemoglobin readily binds to what?