It means that all the organisms in that community rely on one another to survive.
        
                    
             
        
        
        
It is a result of. Erosion
        
                    
             
        
        
        
Answer - B. Kidney function is controlled by the blood's composition and hormones.
Reasoning - Well to start off the kidneys (main) purpose function is to clean your blood which is very Important with blood composition. Second It can also and will excrete it through urine which is pretty much what it does. Oh and also a little bit of hormones. 
 
        
             
        
        
        
Explanation:
The statistical study of populations and how they change over time is called demography. Two important measures of a population are population size, the number of individuals, and population density, the number of individuals per unit area or volume.