Answer:
adrenaline is the hormone which is directly controlled by nervous system
 
        
             
        
        
        
The biological basis for assigning all human beings into a singe species is that there so many, even tons of living organisms living on earth. These organisms differ in their external and internal organs and so to differentiate them from them, they are being classified into kingdoms then classes then phylums then family.
        
             
        
        
        
The process is photosynthesis
        
                    
             
        
        
        
Answer;
Iodine 
A diffuse, nontoxic goiter is usually due to a lack of Iodine in the diet.
Explanation;
-A diffuse non-toxic goiter is an enlargement of the thyroid gland without nodularity. It occurs in an endemic and sporadic distribution. It does not result from an inflammatory or neoplastic process and is not associated with abnormal thyroid function.
-Simple nontoxic goiter, which may be diffuse or nodular, is noncancerous hypertrophy of the thyroid without hyperthyroidism, hypothyroidism, or inflammation. Except in severe iodine deficiency, thyroid function is normal and patients are asymptomatic except for an obviously enlarged, non tender thyroid.