Why are old growth forests considered “healthy” ecosystems?

Which of these serves as a reference for comparison during a scientific investigation? a)outcome variable (dependent variable) b) test variable (independent variable) c)control group d)hypothesis

Predict the results of a two base insertion or deletion in a strand of dna that codes for a protien, how does this differ from a three base insertion or deletion?

It is believed that europa, one of jupiter’s moons has an ocean beneath its surface. based on how earth’s oceans and atmosphere are believed to have formed, what can be said about europa’s supposed ocean? the arrival of in the early days of europa’s existence could have formed its ocean. it is likely that the water experienced , similar to earth. it is also possible that this water is retained beneath europa’s surface and in its atmosphere due to europa’s .