Scientists collect information that allows them to make evolutionary connections between organisms. Similar to detective work, scientists must use evidence to uncover the facts. In the case of phylogeny, evolutionary investigations focus on two types of evidence: morphologic (form and function) and genetic.
 
        
             
        
        
        
The collecting tubules,then into the calyces
        
                    
             
        
        
        
A scientific model is a claim or a theory that helps explain how a phenomenon works or how it undergoes process. This models provides scientists an understanding of the object or a situation undergoes change and generate certain outcomes or effects.
        
             
        
        
        
Well, MOST pathogenic bacteria is harmless, but SOME could cause death, like tuberculosis, but just in case you would want to mark the answer as, "True". 
I hope I helped! =D