Answer:Amphibians evolved during the middle of the Devonian period (416 to 359 million years ago) from the lobe-finned fish of the vertebrate class Sarcopterygii. Species within the genus Ichthyostega (members of the Labyrinthodontia subclass) are considered by some scientists to be the earliest amphibians.
Explanation:
 
        
             
        
        
        
Respiration is process where plant produce heat  
Explanation:
Respiration is essential component for every living thing this. Respiration help living thing get energy and stay alive. In plant cellular respiration is used to convert nutrient which is present in soil and this process can be understand as a cellular activity. In plants seeds play vital role. 
The basic difference between respiration and photosynthesis is in respiration plant consume nutrient for survival and alive plant cell but in photosynthesis plant is able to make their own food.  In respiration only plant produce heat energy
<u>The formula of Respiration:
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Oxygen + glucose – Carbon dioxide + water + heat energy  
<u>The formula of Photosynthesis
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Carbon dioxide + Water + Sunlight – Oxygen + glucose  
 
        
             
        
        
        
Answer:
The metabolic chemical reaction is reversible, and they too would attain equilibrium if they take place in a test tube separately. However, if a cell attains metabolic equilibrium it is considered as dead. Thus, a cell in the body is not in equilibrium.  
The spontaneous flow of substances within and outside of the cell prevents the metabolic pathways from attaining an equilibrium, and the cell persists to perform the work all through its life. This principle is demonstrated by the open hydroelectric system.