Spirilla bacteria are Gram-negative bacteria that may cause bacterial diarrhea, adenocarcinoma and peptic ulcers.
        
             
        
        
        
Introns because they are coding sequences.
Exons because they are non-coding sequences.
        
             
        
        
        
Answer:
Many rare and/or endemic species exhibit one or more of the following attributes which make them especially prone to extinction: (1) narrow (and single) geographical range, (2) only one or a few populations, (3) small population size and little genetic variability, (4) over-exploitation by people
 
        
             
        
        
        
The lowest and thickest layer of the atmosphere is troposphere
        
                    
             
        
        
        
A habitat defines the interaction of organisms with the other factors, which can be living or non-living, while niche describes how that specific organism is linked with its physical and biological environment. Habitat is the part of the ecosystem, while niche plays an important role in the formation of an ecosystem.