Answer:
React on cell surfaces, catalyze reactions.
It provides an objective, standardized approach to conducting experiments and, in doing so, improves their results. By using a standardized approach in their investigations, scientists can feel confident that they will stick to the facts and limit the influence of personal, preconceived notions.
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Modern humans have been the only species of homo, so true .
When we discuss superposition in biology term then its principle tells that one by one rocks or sediments settles.The superposition mean that the older rocks or sediments place below all newly coming sediments or rocks place on first layer so layer over layer formation is called superposition.