Carbohydrates are one of the three primary macronutrients and are chemically composed of carbon, hydrogen, and oxygen. They exist in various forms, including simple sugars (monosaccharides and disaccharides) and complex starches (polysaccharides). The body breaks these down into glucose to provide immediate or stored energy for physiological functions. While fats and proteins are also essential macronutrients, they do not contain sugar as their fundamental structural unit.

Zinc is an essential trace mineral that plays a critical role in supporting the immune system. It is involved in the development and function of immune cells, helping the body fight off infections and promoting wound healing. Deficiency in zinc can lead to a weakened immune response, making individuals more susceptible to various illnesses and infections.

Amino acids are linked together by peptide bonds to form polypeptide chains, which constitute the structure of proteins. A peptide bond is a covalent chemical bond formed between the carboxyl group of one amino acid and the amino group of another, releasing a molecule of water in the process. Although the term used in the option is 'Peptic', it refers to the peptide bond, which is the fundamental linkage in protein synthesis.

Sugary foods, baked goods, and sweet treats are primarily composed of simple carbohydrates. These substances are quickly digested and absorbed by the body, providing a rapid increase in blood glucose levels, which serves as a primary energy source for cellular activity.

Vitamin D is essential for the absorption of calcium and phosphorus, which are critical for maintaining bone health. A deficiency in Vitamin D leads to inadequate mineralization of the bone matrix, resulting in rickets in children, characterized by soft and weak bones. In adults, this deficiency can lead to osteomalacia. Adequate sunlight exposure and dietary intake are necessary to prevent these skeletal disorders and ensure proper bone development.

Marasmus is a severe form of malnutrition caused by an inadequate intake of protein and overall calories. It is characterized by significant muscle wasting, loss of subcutaneous fat, and stunted growth. Protein is a vital macronutrient required for tissue repair, immune function, and structural development in the human body.

Amino acids are the building blocks of proteins, characterized by an amino group and a carboxyl group. Glutamic acid, aspartic acid, and glutamine are all amino acids or their derivatives. Palmitic acid, however, is a saturated fatty acid, which is a lipid component rather than a protein component. This distinction is fundamental to understanding macronutrient metabolism in sports nutrition.

Calcium is a vital mineral that provides the structural framework for bones and teeth. Adequate intake is essential for maintaining bone density and preventing conditions like osteoporosis throughout an individual's life.

Milk is widely recognized as a primary dietary source of calcium, a mineral essential for the development and maintenance of strong bones and teeth. Calcium also plays a critical role in muscle contraction, nerve transmission, and blood clotting. Regular consumption of dairy products is recommended by health organizations to ensure adequate calcium intake, which is vital for preventing conditions like osteoporosis and supporting overall skeletal health throughout the human lifespan.

Riboflavin is chemically known as Vitamin B2. It is a water-soluble vitamin that plays a critical role in energy production, cellular function, and the metabolism of fats, drugs, and steroids. It is essential for maintaining healthy skin, lining of the digestive tract, and blood cells.