Answer:
is the spread of something more widely 
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There are many internal factors which living organisms respond to, two of them are temperature and hormone levels. Organisms respond to internal factors in order to stay healthy and survive. The internal environment of living organisms has to be kept relatively constant, this is constancy is achieved through the process of homeostasis.
        
                    
             
        
        
        
Kinases. Kinases add phosphate to molecules, and the modification can serve as a "switch" to turn events in the cell on or off. CDKs or cyclin dependent kinases regulate the cell cycle.
        
                    
             
        
        
        
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:
 
        
             
        
        
        
The building blocks of protein are C. AMINO ACIDS.
Amino acids are made up of a center carbon atom bound positively to a charged amino group and a negatively charged carboxyl group and a side chain.
The primary structure of a protein is the sequence of an amino acids that are attached together by a peptide bond
The secondary structure of a protein,  the polypeptide is folded through the  mechanisms of amino acids rotating around bonds folding into a helix or a pleated sheet structure and stabilized by a hydrogen bond.