Which of the following is not a function of proteins?
A. Formation of hair, wool, skin, and nails.
B. As a biological catalyst in the form of enzymes.
C. As food in the form of meat, eggs.
D. As an energy provider for metabolism.
Protein maintains the health and quality of the skin by promoting hair follicle growth and keratinization, and thus reducing the likelihood of skin problems. Also, protein is responsible for the formation of wool and nails in animals.
Many proteins are enzymes that catalyze biochemical reactions and are vital to metabolism.
Food in the form of meat and eggs are rich sources of protein.
Protein is not an energy provider for metabolism as glucose is responsible for providing energy for metabolism.
Hence Option D is the correct answer.