Paul Andersen describes four important homeostatic loops in biology. He begins with a brief description of the elements of a homeostatic loop. He then describes how the hypothalamus helps us maintain a stable internal body temperature....

Paul Andersen explains how organisms regulate their internal osmolarity or not. He starts with a brief description of osmosis and why it is important for animal cell to be surrounded by an isotonic solution. He then explains how...

Osmosis is the movement of water across a semipermeable membrane from a region of lower solute concentration to higher concentration. Tonicity refers to how an extracellular solution affects a cell’s water content, described as...

Did you ever wonder what happens to artificial sweeteners when you consume them in food? In this video, we track the fates of two of them (erythritol and sorbitol). They cause loose stool, but they can have other functions as well.