I was gonna try to help but then i realized i need help on the same question l m ao   Explanation:
 
        
                    
             
        
        
        
Answer:
b. They express the appropriate receptor.
Explanation:
The signal transductions are extraordinarily specific and sensitive. Specificity is achieved by a <u>precise molecular complementarity between the signal molecules and the recepto</u>r. For example, the thyrotropin-releasing hormone produces a response in cells of the adenohypophysis, but not in hepatocytes, which lack the receptors to this hormone.
 
        
             
        
        
        
When the blending of traits occurs,<u><em> it is referred to as the principle of incomplete dominance.</em></u>
 
        
                    
             
        
        
        
The root contains hormones that make it grow away from the sun