Answer:
DNA replication needs to occur because existing cells divide to produce new cells. Each cell needs a full instruction manual to operate properly. So the DNA needs to be copied before cell division so that each new cell receives a full set of instructions!
 
        
             
        
        
        
Messenger RNA (mRNA) molecules carry the coding sequences for protein synthesis and are called transcripts; ribosomal RNA (rRNA) molecules form the core of a cell's ribosomes
 
        
             
        
        
        
Answer:
natural
Explanation:
All organisms have a natural habitat in which they live
 
        
             
        
        
        
Answer:
Photosynthesis 
Explanation:
Photosynthesis is the process by which green plants use sunlight to produce their food