Just say we have a big amount of tryptophan in the sense that it exceeds, tryptophan would act as a co-repressor which prevents synthesis of more enzymes for its production
Hope this helps :)
        
             
        
        
        
Multi cellular colonies of plant cells adhere to each other primarily by cell walls, whereas multi cellular colonies of animal cells are typically held together by  proteins
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Explanation:</u></h3>
The organisms that contains more than single single are called as multi cellular organisms. They are just opposite to the uni cellular organisms. When many identical organisms groups to form together it is called as colonies. 
It will be difficult in removing any organisms that forms colonies with the multi cellular organisms.The multi cellular organism of the cells in the plants are bonded to each other with the help of the cells walls. In animal cells these are bounded together with the help of the proteins.
 
        
             
        
        
        
Answer:
 A: Bioaccumulation
Explanation:
It accumulates (builds up) in you, its bioaccumualtion.