Answer:
The exons may be defined as the coding region of the RNA that codes for the particular amino acid. The introns are the non coding region of RNA and must be removed in the final RNA product.
Exon shuffling result in the formation of new gene. The alteration of the exon and intron structure leads to the new gene function in evolution. The genes that are favored and conserved in the evolution perform new gene function. The genes that are selected against are deleted during the evolution. 
 
        
             
        
        
        
Phototropism as photo means light
eg: photosynthesis
        
             
        
        
        
I think the answer to this is abyssal plane 
        
                    
             
        
        
        
Answer:
The answer would be D. Tropical Rain forests comprise only 6% of all land on Earth yet are home to nearly 50% of all the species on Earth.