Supplemental amino acids can be given intravenously to preterm infants to stimulate growth. By which of the following direct mechanisms might these supplemental amino acids help promote growth?

While lipids are an important macronutrient, amino acids are not directly converted into lipids. Instead, lipids are primarily synthesized from fatty acids and glycerol. Thus, this option misrepresents the primary role of amino acids, which is not to create lipid structures.

Carbohydrates are primarily formed from monosaccharides and polysaccharides rather than amino acids. Although amino acids can participate in gluconeogenesis under certain conditions, their main function is not to synthesize carbohydrates. Therefore, this option does not accurately reflect the direct mechanism by which amino acids promote growth.

Nucleic acids, such as DNA and RNA, are primarily composed of nucleotides, which include a sugar, a phosphate group, and a nitrogenous base. While amino acids are involved in various cellular functions, they are not used to synthesize nucleic acids directly. Thus, this choice does not represent the primary role of supplemental amino acids in promoting growth.