Answer:
Respiration is a process in which energy is released due to the breakdown of glucose molecules with the addition of oxygen forming carbondioxode, water and energy in the form of Adenine tri phosphate (ATP). In respiration process, carbondioxide is released in the atmosphere and oxygen is used for breakdown of food. This carbondioxide is used by the plants in the process of photosynthesis and oxygen is released in the atmosphere which is again used by animals for respiration. 
 
        
             
        
        
        
Answer:
In order, from least complex to most complex:
cells.
tissues.
organs.
organ systems.
organism.
Explanation:
 
        
             
        
        
        
Infected cells create and release small proteins known as interferons, which help the immune system fight viruses. Interferons stop viruses from replicating by interfering with their ability to multiply within infected cells.
        
             
        
        
        
Answer:
Numerous examples of this human-induced contemporary evolution have been reported in a number of 'contexts', including hunting, harvesting, fishing, agriculture, medicine, climate change, pollution, eutrophication, urbanization, habitat fragmentation, biological invasions and emerging/disappearing diseases.