It is a hollow ball of cells formed after a fertilized cell undergoes cell division.
I'm a Biology major, hope I helped :)
        
                    
             
        
        
        
Solar power because it is never ending and has no emmisions
        
             
        
        
        
Allele frequencies in a population may change due to four fundamental forces of evolution: Natural Selection, Genetic Drift, Mutations and Gene Flow. Mutations are the ultimate source of new alleles in a gene pool. Two of the most relevant mechanisms of evolutionary change are: Natural Selection and Genetic Drift.
 
        
                    
             
        
        
        
Answer:
In an allergic response, which substance initiates inflammation?
Histamine initiates inflammation in an allergic response
Explanation:
Histamine is a chemical that is being released during allergic response which initiates inflammation
 
        
                    
             
        
        
        
Answer:
D and E
Explanation:
The others are physical methods and can be separated again.
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