A)Enzymes speed up reactions that help sustain life
        
                    
             
        
        
        
Answer:
<u>C) They may provide selective advantages.
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<u>D) Slight differences in the genetic code may have significant results.</u>
Explanation:
The genetic code is universal, and present in most living beings . Generally, in most living organisms, the same codons are assigned to the same amino acids.  
DNA sequences make up genes that may have multiple variants, called alleles. DNA deoxyribonucleic acid, is transcribed into mRNA and then translated into amino acids that form proteins. 
Natural selection mainly acts on phenotypes, which are dependent on proteins and the organisms's environment.  Phenotypes conferring advantageous traits are favored by the selection process- these help groups of organisms evolve over time.
 
        
                    
             
        
        
        
A. U - A - C
B. A - U - G
C. Adenosine, Uracil, Guanine
 
        
             
        
        
        
<span>Molecular clocksC. take advantage of known mutation rates to estimate how long ago organisms shared a common ancestor.
All of the following are important properties of prokaryotes except
A. prokaryotes are used to make many products for humans.
All of the following patterns were witnessed by Darwin except that species vary
C. within very short spans of time.
The scientific name for a white oak is Quercus alba; the scientific name for a red oak is Quercus rubra.What does this tell you about the organism?
D. White oaks are grouped in the same species category as red oaks.<span>
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