Answer:
Option D
Explanation:
Bits of DNA that are interspersed among these repeated sequences are called spacers. Regarding to bacteria, the spacers are taken from viruses that previously attacked the organism. They serve as a bank of memories, which enables bacteria to recognize the viruses and fight against future attacks.
 
        
             
        
        
        
Because the dark box is blending in with the shadows, however the white box is bright and easier to see
 
        
             
        
        
        
Catalysts are substances that cause a chemical reaction to occur in a different way than it would otherwise happen without that catalyst – a catalyst could cause a reaction to happen at a faster rate, or at a lower temperature, than would be possible without the catalyst.<span>
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