My guess is that fat-soluble toxins that may occur in freshwater ecosystems would most affect apex species in these ecosystems. This is because fat-soluble toxins are stored in the fat reserves of animals, and then bioaccumulate up the food chain. So in this case, most of the toxin is not secreted, but stored within the food chain, and bioaccumulates, with the concentration becoming higher the further up the food chain. 
        
                    
             
        
        
        
Answer: Meselson & Stahl reasoned that these experiments showed that DNA replication was semi-conservative: the DNA strands separate and each makes a copy of itself, so that each daughter molecule comprises one "old" and one "new" strand. The semi-conservative model, in which each strand of DNA serves as a template to make a new, complementary strand, seemed most likely based on DNA's structure. ... From the patterns of DNA labeling they saw, Meselson and Stahl confirmed that DNA is replicated semi-conservatively.
Explanation:
 
        
             
        
        
        
Answer: Option B) No, even though the DNA sequence changed, the sequence still codes for the same amino acid, so no change in phenotype will occur. 
Explanation:
Since the triplet codon ACG codes for the amino acid threonine, so also ACA codes for threonine, the single base change of Guanine (in ACG) to Adenine (ACA) is insignificant due to the degeneracy of the genetic code.
Thus, the sequence still codes for the same amino acid, so no change in phenotype will occur
 
        
             
        
        
        
Proteins can denature at extreme temperatures, or denature when inhibits are present. When this happens their functionality is dramatically reduced.
        
             
        
        
        
Grams is much denser then kilograms 
please give it the brainiest answer