Virus are made with ADN or RNA only, which both of them has the information of replication. Once that the virus is in a cell, this ADN or RNA will be deposit inside the cell at the replication system that is going to make the virus reproduce unlimited times until the membranes of the cell break down. And they are useful because you can use them as a carrier or vector for treat diseases or for transgenics, bioterrorism, and so on.
        
             
        
        
        
Answer:
Pathogenic bacteria are bacteria that can cause disease. Although most bacteria are harmless or often beneficial, some are pathogenic, with the number of species estimated as fewer than a hundred that are seen to cause infectious diseases in humans
Explanation:
 
        
                    
             
        
        
        
Answer: C
Explanation: DNA polymerase is the enzyme that matches and lays down nucleotides to build the daughter DNA strand along each parent DNA strand. Now we're left with all these Okazaki fragments that are separate from each other, so they need to be joined together by the enzyme DNA ligase
 
        
             
        
        
        
The atoms are going through decomposition.They are breaking apart into the elements they are made of.