Close your eyes for a few seconds and ask yourself “what am I doing right now?”
If the only answer you came up with was “nothing”, try again.
If the answer is still nothing, then you should probably drop this class and take a course in existential philosophy.
You can probably think of quite a few things, but even still there are countless others. Each of the activities you listed is made possible by a multitude of physical mechanisms and biochemical pathways that allow each of the individual cells in your body to contribute to an organized mission, whose object is to keep you alive and perpetuate the genetic instruction manual that can guide the development of a human.
You can probably think of quite a few things, but it is most likely only the tip of the iceberg. Each of the activities you listed is made possible by a multitude of physical mechanisms and biochemical pathways that allow each of the individual cells in your body to contribute to an organized mission, whose object is to keep you alive and perpetuate the genetic instruction manual that can guide the development of a human.
And if that isn’t complicated enough, think about the fact that humans are not the only complex organisms out there. Our planet is alive not only with non-human species but also with biochemical processes, sensory mechanisms, anatomical features, and behaviors that do not occur in humans.
This course is a hopeless attempt to dive into this diversity and learn about the mechanisms that make complex organisms work and the evolutionary forces that shape those mechanisms. The effort is hopeless in the sense that a full understanding of physiology is beyond the reach of a single lifetime of study, or even the concerted efforts of the army of scientists who make it their life’s work, let alone a one semester course. But it is still a worthy effort. What you learn in this course will help you understand how your body works and how it came to be. Also, we will investigate some amazing critters that are pretty cool in and of themselves.
Physiology is a huge field of knowledge and research. To make things a bit less overwhelming, we are going to start with simple phenomena that work on a very small scale and then progress toward larger more complex stuff. In this case, “small scale” means “molecular scale”. Physiology in the modern world is intimately concerned with how molecules interact. As we will see later on in this book (or whatever it is), molecules–especially proteins–are the cogs, wheels, and moving parts that allow complex organisms to perform complex tasks. Once we get a feel for how some of the major molecular mechanisms operate, we will look at higher-level functions that operate on the cellular and tissue levels of organization. Then we will work through some major organ systems and ultimately progress into the physiology that underlies whole-organism behavior.
Sound OK? Let’s get started.