Answer:
The four main classes of organic compounds (carbohydrates, lipids, proteins, and nucleic acids) that are essential to the proper functioning of all living things are known as polymers or macromolecules. All of these compounds are built primarily of carbon, hydrogen, and oxygen but in different ratios.
Explanation:
 
        
             
        
        
        
Answer:
There is less biodiversity in the ecosystem.
Explanation:
Since the barren ground doesn't provide suitable living conditions for most of the living organisms, the ones that need the lest resources to survive create the primary succession, usually the mosses and lichens. The organisms of the primary succession provide biomass, so the ground is mixing with it, thus new soil is forming. 
 
        
                    
             
        
        
        
Answer:
the answer will be 
measure the growth of plant that did not recieve fertilizer
perform additional trials
Explanation:
i just took the test and got the answer right
 
        
                    
             
        
        
        
It shows evolution and growth from the past and present
        
             
        
        
        
Answer/Explanation:
b) kidney and bladder
Kidneys are the main organ in the excretory system and the bladder stores the urine in the body. These are two of the organs that make up the excretory system.