IF YOU ARE REFERRING TO YEAST INSIDE THE AREAS NECESSARY FOR FEMALE REPRODUCTION: Yeast isn't necessarily "helpful" or "not helpful." Its similar to bacteria in your mouth. There is nothing harmful about yeast it just simply exists so long as you have the parts where it lives. It will kill any general form of other bacteria foreign to it, but when more yeast is produced than is normal for a woman, like when taking antibiotics, after pregnancy, or changing hormone suppliments (Birth Control), your body is told to produce more yeast, causing a yeast infection. SO if that wasn't what you were asking about... I apologize for the images or thoughts I forced you to think about. If it was... I would be happy to give you some more info, just ask!
mould is a helpful one and bacteria is a harmful one
If you need help I recommend you type in the specific question you need help with
Bacteria would consider benefitial and harmful bcz many food component are you eating made by bacterial reactions like yeast... but most of spp. are harmful.
it can be helpful or harmful
sometimes they are helpful and harmful.
is yeast dangerous or harmful
Sandpaper is both helpful and harmful.
they are helpful not harmful to plants
helpful
helpful
Depends on what part of "harmful" or "helpful" you are referring to.
Harmful bacteria will harm you. Helpful bacteria will help you.