Would you classify bacteria as harmful or helpful?

I will classify bacteria as harmful because it always harms our body by different way but I think any how it also helpful

the calvin cycle has three stages. in stage 1, the enzyme rubisco incorporates carbon dioxide into an organic molecule. in stage 2, the organic molecule is reduced. in stage 3, rubp, the molecule that starts the cycle, is regenerated so that the cycle can continue

what school and grade?