Final answer:
Amino acids combine to form proteins by forming peptide bonds through dehydration synthesis, where water is released. Proteins are broken down through hydrolysis, adding water to peptide bonds to separate amino acids.
Step-by-step explanation:
Amino acids are organic molecules essential for creating proteins. They are linked by a peptide bond, a covalent bond formed during a dehydration synthesis reaction. This process occurs when the carboxyl group (-COOH) of one amino acid reacts with the amino group (-NH₂) of another, releasing a water molecule and forming an amide linkage. The product of two joined amino acids is called a dipeptide, while longer chains are known as polypeptides. A protein is composed of one or more long polypeptide chains. The bond forms between the carbonyl carbon of one amino acid and the nitrogen of another, continually extending the protein chain with the addition of more amino acids.
The breakdown of proteins happens through hydrolysis, which reverses the dehydration synthesis process. Water is added back to the peptide bond, resulting in the separation of the amino acids. This is typically catalyzed by enzymes in organisms and is crucial for protein digestion.