The flow of energy in an ecosystem is best described as energy moving in one direction from the sun to the producers then to the consumers. 
Explanation; 
Energy flow is the amount of energy that moves through successive trophic levels of a food chain in an ecosystem. Ecosystem maintain themselves by cycling energy and nutrients. 
The energy from sunlight is taken up by producers which use it to produce organic compounds through photosynthesis. The energy is then passed successively to the trophic levels, that is from the producers to the consumers ( primary, secondary, tertiary and quotienary consumers). During this transfer some energy is lost at each trophic level in form of heat. 
        
                    
             
        
        
        
Answer: One difference is that eukaryotic cells have a membrane-bound nucleus and prokaryotic cells do not. Another difference is that eukaryotic cells have many membrane-bound organelles while prokaryotic cells have no membrane-bound organelles.
Hope this helps! :)
 
        
             
        
        
        
Answer:
life will not possible on Earth I think so
 
        
                    
             
        
        
        
C.) depend on the same resources
Competition is the rivalry between living things for territory, resources, goods, mates, etc. It is a symbiotic relationship that occurs in nature. Same or different members of species compete for resources, especially for limited natural resources.
 
        
             
        
        
        
Answer:
This cycle takes approximately 100,000 years to complete.
Explanation:
PLATO