We share the earth with millions of weird and wonderful living things. All uniquely adapted to their own particular environments. Yet, despite our differences, we all have one thing in common. Our survival, everything we do relies on complex internal processes that, when working well, allow us to respond to the challenges of everyday life. The study of these mechanisms is called Physiology The Science of Life With construction, if you want to make a building certain elements have to be assembled in a particular order for it to work properly. But you can make a huge variety of buildings from those same elements. It's similar with living organisms DNA dictates that the same essential blocks of life: molecules, cells, and, in higher animals, tissues, organs and whole body systems, work together in different ways to respond to different environments and challenges. By developing a picture of how these interactions work and how they maintain a delicate balance, such as blood pressure or body temperature, physiologists are answering big questions about what keeps us healthy. Such as, how artifical light might impact our sleep cycle. If you grab your phone in the middle of the night, the light from the screen hits cells in the retina of your eyes. Physiologists are studying how signals from those cells to your brain at the wrong time of day could alter the normal release of hormones, leading to disturbed sleep. Sports physiologists are investigating how exercise can improve how our bodies work. For instance, how our hearts change, to pump more blood with each beat, so improving our performance. You can even find physiologists in space, researching the effects of zero gravity on how the body works, which will come in handy when we want to explore other planets. Here's the thing, every time we take a breath, open our eyes, or take a step, we don't think of the scientific forces at play. That is, until things go wrong, when one or more of the components stop working properly. Thankfully, discoveries made by physiologists inside and outside the lab, provide core information for doctors, dentists and vets both in their everyday work and in tackling some of the greatest health challenges we face today, such as uncovering the impact of air pollution. How toxic chemicals in the air we breathe disrupt the uptake of oxygen into our bodies. And teasing apart the mechanisms for obesity. Studying mice, physiologists have found that messages from the gut to the brain saying it's full can get disrupted. so the individual just keeps eating, becoming ever more obese. Physiologists are working to solve this and many of life's great mysteries. But there's still lots left to discover and now is a fantastic time to get involved, to help tackle some of these global issues.