Final Answer:
Lysine is the amino acid that rice and other grains typically lack, making them incomplete proteins. Thus the corect option is 1.
Step-by-step explanation:
Rice and many other grains are considered incomplete proteins because they lack sufficient amounts of certain essential amino acids. Lysine is one such essential amino acid that's often limited in grains like rice. An essential amino acid is one that the body cannot produce on its own and must be obtained through dietary sources. Lysine plays a crucial role in protein synthesis and is necessary for various bodily functions, including tissue repair, growth, and the production of enzymes and hormones.
The inadequacy of lysine in grains like rice makes it essential to combine them with other complementary proteins that contain higher amounts of lysine, such as legumes or animal-based proteins, to form a complete protein. Complementary proteins are two or more food sources that, when combined, provide all the essential amino acids in adequate proportions. By combining rice with legumes like beans or lentils, for example, one can create a balanced amino acid profile, compensating for the lysine deficiency in rice.
Understanding the deficiencies in amino acids within certain foods is crucial for individuals who follow plant-based or vegetarian diets, as it ensures they obtain all essential amino acids for proper bodily function. By combining different protein sources strategically, one can achieve a balanced intake of essential amino acids, overcoming the limitations of individual incomplete proteins like rice in providing a full spectrum of amino acids necessary for optimal health. Thus the corect option is 1.