Answer:
Isotonic contractions maintain constant tension in the muscle as the muscle changes length. This can occur only when a muscle's maximal force of contraction exceeds the total load on the muscle. Isotonic muscle contractions can be either concentric (muscle shortens) or eccentric (muscle lengthens).
 
        
             
        
        
        
Proteins help with acting as structural components in the body, speeding up chemical reactions, and transporting substances around the body. Proteins are made up of amino acids, which create enzymes. Enzymes are often affected by  environmental factors in the body such as concentration, temperature, and pH. 
Proteins are very important for DNA and RNA. (ribonucleic acid)
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C. because if there was no clovers, the mice can not feed, and if the mice can not feed they will starve out and die.
        
             
        
        
        
Their mitochondria do not have an electron trasnport chain and so cannot funciton in aerobic respiration. 
Electron Transport Chain (ETC) essentially makes the energy required for respiration. 
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