Just wanted to share this question and answer with you all, since I’m sure there are other people wondering the same thing.

Q. Do we need to know the specific percentages of everything in the blood lecture? For example, the percentage of water in the red blood cell cytoplasm, and the percentage of each protein within plasma?

A. Good questions! No – I don’t want you to memorize specific numbers. But I would like you to know the relative amounts of things. For example:

1. For red blood cell contents: the most abundant substance inside red cells is water.
2. For plasma proteins: albumin is the most common protein in the plasma.
3. For the number of each type of white blood cell in the blood: Neutrophils are the most common/numerous; lymphocytes are the second most common, monocytes are the third most common, eosinophils are the fourth most common, and basophils are the least common.