6.Distilled water sample is necessary in procedures A and B because it is used as a control sample. Distilled water is used as a control because its purified. Its devoid of contaminants. Controls are needed so you can see what the results would be of an experiment. Positive controls tell you what the positive result of your unknown would be, and negative controls show you what the negative result of your unknown would be when added with Benedict's solution or the Iodine solution. Without the controls, you wouldn't know.

Lipids

1.Fat molecules are made up of a molecule of glycerol and three molecules of fatty acids. Each fatty acid consists of a hydrocarbon chain with a carboxyl group at one end. The glycerol molecule has three hydroxyl groups, each label to interact with the carboxyl group of a fatty acid. Removal of a water molecule at each of these three positions form a triglyceride.

2.Fats, oils and waxes are all lipids. Fats and oils are made from glycerol and three fatty acids joined by dehydration synthesis. (also known as triglycerides). Naturally occurring esters of long chain carboxylic acids with long chain alcohols are waxes. Waxes are low melting point solids.

3.A diet including large quantities of saturated fatty acids should be avoided because saturated fatty acids are a major risk factor for heart attacks and strokes. Diets high in saturated fatty acids lead to an increase in the production of cholesterol. They also lead to health problems including obesity, heart diseases, and cancers of the breast and colon. The build up in the arteries can cause atherosclerosis which leads to major heart problems.
Proteins

1.

2. Denaturing is a process in which the protein loses functionality because bonds are broken and it returns to the primary structure. The causes of protein denaturing include: heat (temperature, fever), pH (interrupts ionic bonds and hydrogen bonds), and high salt concentration.