Photosynthesis produces oxygen and water. Photosynthesis is the result of a cycle. Humans use oxygen for respiration, the product produced from human respiration is carbon dioxide. Then plants absorb carbon dioxide from the air and turn it into oxygen with photosynthesis, this goes on and on as a cycle.
        
             
        
        
        
Factory Emissions is going in the wrong direction. The arrow should be pointing upward, as factory emissions release carbon into the atmosphere. 
        
                    
             
        
        
        
It also plays a key role in shaping organic molecules. Carbon<span> is very </span>important<span> to the chemistry of living things, mainly because of the versatility of structures it can form with itself and with other atoms</span>
        
             
        
        
        
Explanation:
The best-known neurotransmitters responsible for such fast, but short-lived excitatory action are acetylcholine, norepinephrine, and epinephrine while GABA is the major inhibitory neurotransmitter. Neurons are the basic building blocks of the nervous system.