<span>The nitrogen cycle could not exist without first nitrogen. The cycle is about this specific element which goes to show that if this element is not present then, there will not be any nitrogen cycle. Also, an important factor for the cycle is the presence of the bacteria and other microorganism which are needed for the fixation. </span>
The answer is D. 4 because its after perception
The answer is prokaryotic cells and Eukaryotas.
False.
Any time a scientific theory is challenged, it means it's not a good
theory. And this statement is not valid. In theoretical models, they are
revisited when there are further studies and discoveries found in a certain
area where they can be remodeled and reintegrated instead of disregarding its
credibility. Models, theories and paradigms are not challenged but rather
encouraged, they are supported in many studies since these theories and models
were created in order for us to understand a certain phenomenon but it would
likely help the scientific society to be updated in the new forms or spheres of
improvement rather than discouragement.