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Compounds That Compose the Human Body There are five major groups of compounds that compose the human body. They are carbohydrates, lipids, proteins, nucleotides, and water. These are all very important to humans and without them we would not be able to survive. ....

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.... are attached to outer surfaces of cell membranes to guide cellular interactions. For many cells, sugars are the most important source of energy. Lipids are important because they function as structural components of cell membranes, sources of insulation, and a mean of energy storage. The lipid molecules are most well known as forming basic structures of cell membranes and as energy storage molecules as well. In this group of lipids, there are about three main types: true fats (triglycerides), phospholipids, and steroids. True fats represent the body’s most abundant and concentrated source of usable energy. When they are oxidized, they yi ....