The document discusses protein and its sources, including complete, partially complete, and incomplete proteins. It emphasizes the importance of obtaining protein from a variety of sources to meet amino acid needs. It then covers several micronutrient deficiencies that can result from lack of certain foods, including iron, zinc, iodine, and various vitamins. Signs and symptoms of each deficiency are provided along with important food sources of the respective nutrients. Finally, it recommends portions of protein-rich foods for adolescents to aim to eat with each meal.