For use in (aerobic) respiration, polypeptides would first be hydrolysed to their amino acid monomers. These are each deaminated, i.e. have their amino groups removed, producing an organic acid, which can be fed into the Kreb's Cycle, and a waste product, ammonia (NH₃), which is moved to the liver and removed from the blood.
Answer: The role of an organism in the ecosystem is called its NICHE.
Explanation: The niche (pronounced 'neesh') of an organism is the specific function and purpose of the organism within its environment, ecosystem or food-web or food-chain.
The tendon of the long head of the biceps muscle
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