They help an environment because they create an ecosystem allowing animals to thrive and live a lifecycle with the resources they need. 
 
        
             
        
        
        
If in an eight-cell embryo of an organism, the cells of the upper tier are aligned over the cells of the lower tier at a slight angle, it is likely that the organism is a vertebrate. 
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Answer:
To be honest, it's optional so hope these answers will work for ya!
Explanation:
*Earth has atmosphere and life while the moon doesn't
*Earth has weather and seasonal changes
*Moon has satellite's that we set up and use
*Types of erosion:
Earth: wind, water, ice, and heat
Moon: impact
*Landscape:
Earth: of course we all know... -._-.
Moon: craters, dust, and rocks
<em>HOPE THIS STILL WORKS! ˋ( ° ▽、° ) </em>
 
        
             
        
        
        
I believe it is scientific laws.
        
             
        
        
        
There are multiple energy source in the ocean. The one thats probably the most common one are Dams. Although Dams can cause some serious flooding. Another one is Tidal energy. Tidal energy is something that turns the energy of tides into energy through Kinetic motion.<span />