D. The permain. Had the largest mass extinction
        
             
        
        
        
Answer: Ecological footprint 
Explanation:
Ecological footprint simply refers to the ways in which the effect of human activities are measured in terms of the area of biologically productive land and water required to produce the goods consumed and to incorporate the wastes generated. In ecological footprint, there available productive land and water needed to supply the people in a particular country or area with an endless supply of renewable resources and to absorb and recycle the wastes and pollution produced by such resource use. 
 
        
                    
             
        
        
        
The biogeochemical cycles move through mainly the biotic and abiotic components of the earth<span>, more elaborately the spheres -biospheres, lithosphere, hydrosphere and atmosphere regions of the ecosystem. These biogeochemical cycles, from its terminology and discernable word morphology- involves the biological, geological and chemical components that make out to complete an exact and purposed cycle. The purpose in these cycles are to maintain balance and to ensure the ongoing process of the living and non-living organisms in the environment. These cycles’ help to living organisms survive and thrive. One popular example is the water cycle. </span>
        
             
        
        
        
Answer:
integumentery system
Explanation:
your skin is actually the first protection against illness-causing pathogens.
 
        
                    
             
        
        
        
Enzymes are biological catalysts. Catalysts lower the activation energy for reactions. The faster the rate enzymes speed up reactions by lowering activation energy