Cerebrum is in the most anterior part of our brain, fronting of the skull. It functions in sensory and neural processes. Cerebellum is found at the back of the skull. It functions in coordination, balance and muscular activity. Medulla oblongata connects from the spinal cord which controls heart and lungs. Pons is part of the brainstem which controls breathing and communication.
        
                    
             
        
        
        
D: The longest time period it may take to replace a renewable resource is 500 years
        
                    
             
        
        
        
Answer: The most reason was that cell-to-cell communication and the different chemical compositions of the cell walls of plant, fungi, and bacteria restricts the intercellular communication to their own species.
Explanation:
 
        
             
        
        
        
Small, but normal variations in genes may produce proteins that work differently from those of other individuals ( friends or relatives). This may affect how we respond  to different medicines. The extent to which these proteins functions varies from one individual to another. Example; certain painkillers only work when body proteins convert them from an inactive form to an active one. If these proteins work too fast, the drug will be eliminated from the body before it has time to work. To do their job the pain killers need to bind and modulate a target body protein, the receptor, such that if the target body protein is altered the pain killer might not be able to bind. 
        
             
        
        
        
Alright my friend so the sister chromatids separate and each daughter cell gets one chromosome during the Anaphase