How do snails, seeds, bears, zooplanktons, fungi and bacteria adapt to conditioins unfavourable for their survival?

How do fungi obtain their food ?

How do microbes survive adverse conditions?

Bear hibernates whereas some species of zooplanktons enter diapause to aviod stressfull external conditions. How are these two ways different from each other ?

How do bacteria causing typhoid enter body.

how are cactus adapted to survive in a desert?