AP BIOLOGY

Detailed explanation-1: -In molecular biology, protein catabolism is the breakdown of proteins into smaller peptides and ultimately into amino acids. Protein catabolism is a key function of digestion process. Protein catabolism often begins with pepsin, which converts proteins into polypeptides. These polypeptides are then further degraded.

Detailed explanation-2: -Protein catabolism is the breakdown of proteins into absorbable monomers for further degradation or reassembly. Protein catabolism in the intestinal lumen is important for several reasons, one of which is mobilizing essential amino acids for absorption.

Detailed explanation-3: -Catabolism of amino acids can be broadly categorized into two processes: the breakdown of amino acids to carbohydrate precursors and potentially leading to the formation of glucose; and transformations leading to acetyl CoA that result in the potential formation of ketone bodies.

Detailed explanation-4: -Proteins are the polymers of amino acids. So, the first product of protein catabolism is ammonia, followed by urea and carbon dioxide, amino acids are the end products.