Which statement best describes ecosystems? A. they can never change once they are established
B. they constantly change in different ways over time
C. ecosystems always revert back to their original state
D. each ecosystem can exist for only a specific lenght of time

Amylase becomes denatured at a temperature of 80°c. during an experiment to study the effect of varyingtemperature on enzyme activity, amylase’s reactivity with starch was measured at body temperature (37°c), andthen again at an increased temperature of 42°c. how would this increase in temperature affect the experiment

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm

Which zone within the open-ocean zone is home to the most organisms? deep zone surface zone intertidal zone transition zone