Blood urea nitrogen (BUN) is a measure of the amount of urea in the blood (R). It provides useful information about your health. The liver produces urea as a waste product of the digestion of proteins (R, R). Urea is a safe vehicle to get rid of excess nitrogen from the body.
Algebra is a branch of mathematics that substitutes letters for numbers, and an algebraic equation represents a scale where what is done on one side of the scale is also done to the other side of the scale and the numbers act as constants.
Pre-algebra is a common name for a course in middle school mathematics. In the United States, pre-algebra is usually taught in the 7th grade. The objective of pre-algebra is to prepare the student for the study of algebra. Pre-algebra includes several broad subjects: