Final answer:
Non-essential amino acids are synthesized by the body and are vital for protein synthesis, serving as neurotransmitters, contributing to metabolic pathways, and supporting the immune system and gut health.
Step-by-step explanation:
Non-essential amino acids are amino acids that the human body can synthesize on its own, which means we do not necessarily need to get them from our diet. These non-essential amino acids still play a vital role in various bodily functions. They are involved in protein synthesis, which is crucial for tissue repair and growth. Some non-essential amino acids also partake in metabolic pathways, serve as neurotransmitters, or contribute to immune function. For example, glutamine is a non-essential amino acid that is crucial for immune cell function and gut health. Alanine assists in energy production by contributing to the glucose-alanine cycle. Furthermore, under certain conditions or stages of life (such as infancy, sickness, or stress), these non-essential amino acids can become conditionally essential, meaning that the demand increases to a level that cannot be met by the body's synthesis alone and thus must be obtained from the diet.