Answer:
Explanation:
The two categories of the behavior includes the operant behavior and respondent behavior.
Operant behavior: The operant behavior can be define as the behavior that is under the control of the consequences. These consequences are likely to control the future frequency of behavior. For example, A child who is allowed to hit other children and take their toy, is likely to be aggressive to other people in the future.  
Respondent Behavior: The behavior which is under the influence of a specific stimuli is a respondent behavior. For example, Snapping of hand away from a hot pan, and Salivation of the mouth due to food. 
 
        
             
        
        
        
No organism is always the first step, except in a wide sense, plants. In the water, plankton is found in first but whereas on land, plants or seeds are eaten first.
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the skin has cells like that
 
        
             
        
        
        
Cells get raw materials- including water, oxygen, minerals and other nutrients from the foods you eat. They let in raw materials through the cell membrane: the thin, elastic structure that forms the border of each cell.