Avoiding Surcharges. Because airlines charge a peak travel day surcharge on the most popular days of travel -- Sunday, Monday and Friday -- you can get the best discounts on those off-peak days. However, during the summer, peak and off-peak travel days do not really exist.
Proteins are essential nutrients for the human body. They are one of the building blocks of body tissue, and can also serve as a fuel source. As a fuel, proteins contain 4 kcal per gram, just like carbohydrates and unlike lipids, which contain 9 kcal per gram.
The function of proteins. In virtually every biological process proteins are playing a role. According to a report published in the journal Molecular Biology 2, some of the main functions of proteins in the human body are to: 1  Build, strengthen and repair/replace things, such as tissue.