Final answer:
The Institute of Medicine's Recommended Dietary Allowances for proteins depend on body size, with the daily requirement varying by individual factors like weight and age. Essential amino acids must be consumed through the diet as they are pivotal for protein synthesis. Proteins also serve as an energy source, contributing 4 Calories per gram.
Step-by-step explanation:
The Institute of Medicine's Recommended Dietary Allowances for proteins are tailored to meet an individual's nutritional needs. The correct answer to the question is: b. They are relative to a person's body size. This is because the protein requirements vary depending on several factors, including body weight, age, and growth rates. Proteins are essential nutrients comprised of amino acids, which are necessary for synthesizing new proteins, body repair in adults, and body building in children. While the body can synthesize some amino acids, there are essential amino acids that must be obtained through the diet. These amino acids are critical as they are the building blocks for protein synthesis in the body.
Proteins from the diet are broken down during digestion into amino acids and absorbed by the body. These are then used for various functions like building muscles, enzymes, and antibodies, or are excreted if not required. Remember that proteins also provide energy, with one gram of protein supplying 4 Calories.