We have as many bacteria as human cells.
Why it is true
The body hosts trillions of microorganisms (microbiome) that coexist in symbiosis, vital for immunity and digestion.
Source: Scientific Research
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.