Answer:
The answer is option C : a bacterium 
 
        
             
        
        
        
Elephants, who are important grazers, are instrumental in transforming woodlands into grasslands. This has a tremendous impact on other species that depend on the grass for their survival. The significance of the elephant in this example is B. keystone species. 
        
                    
             
        
        
        
Answer:
Glucose circulates in the blood of animals as blood sugar. It is made during photosynthesis from water and carbon dioxide, using energy from sunlight. It is the most important source of energy for cellular respiration.
Explanation:
Glucose is formed in blood cells.
 
        
             
        
        
        
Answer:
Here's Why:
Explanation:
In living cells there are hundreds of different enzymes working together in a coordinated manner, and since cells neither synthesize nor break down more material than is required for normal metabolism and growth, precise enzyme regulation is required for turning metabolic reactions on and off.