Final answer:
The statement is true; once protein digestion is complete, amino acids are available for the body's use. These freely circulating amino acids can then contribute to an array of critical biological functions, including synthesis of new proteins, enzymes, and other essential molecules.
Step-by-step explanation:
Once digestion of protein is completed, amino acids will indeed be available for our body's needs. This is a true statement. Proteins from the diet are digested into their amino acids, which are the building blocks for synthesizing new proteins within the body. These amino acids are then used for various critical functions such as building and repairing cells, fighting infection, and synthesizing new proteins and other nitrogen-containing compounds like DNA bases, neurotransmitters, and hormones. It is important to note that not all amino acids can be synthesized by the body; some known as essential amino acids must be obtained through our diet, as the body cannot produce them. Also, proteins cannot be directly obtained from food and must be broken down into amino acids before our bodies can use them. Lastly, amino acids are not stored by the body for long and are quickly recycled or converted into energy if not used for protein synthesis.