Another mixture commonly heard of is blood. If you cut yourself, there it is. Blood is what is called a complex fluid: it is essentially particles suspended in a liquid. These particles are red and white blood cells, and the liquid is what’s called plasma. Blood is 54.3% plasma (by volume), 45% red blood cells, and 0.7% white blood cells.
Plasma is a solution that has a lot of things in it. When you get a blood test, this is what is being measured: the concentrations of many components of your plasma. Shown above is a section of this fantastic logarithmic plot of blood component levels (zoom in and slide back and forth: abundant stuff is to the right, trace components are to the left). Some components of plasma are glucose (sugar), all the different kinds of cholesterol, calcium, bilirubin, vitamin E, etc.
The flow properties of blood are quite complicated, because it is a complex fluid. Studying blood flow is a currently hot area of research. So, if you want to be a scientist, maybe that is something you can study.