There we came to understand what cells are and how they function, as well as what it means to be alive. We’ve also learned about biochemistry in my biochemistry series, so we know about the molecular components of cells, and we understand how chemical processes occur within cells, including how energy is produced. And in my classical physics series we learned all about energy conservation, and the ways that energy can be converted from one form to another, through all of the biological activity that occurs every day, all over the world. But all of this begs the question, where does that energy come from in the first place? Welcome to planet Earth, where all living things owe their existence to green plants that harness energy from the Sun.
That’s right, all the chemical energy organisms use on Earth, except for a few rare and funky exceptions, is harnessed by plants. So if we want to understand how energy from the Sun becomes food and fuel for all the rest of us, we will need to study botany. And that’s what we are going to do here in this botany series. We are going to build upon what we already know about biomolecules and cellular processes, and take a deep dive into the world of plants. If you’re a little rusty on your principles of biology, but you don’t feel like watching dozens of tutorials before moving forward here, not to worry.
Whenever prior knowledge is referenced and assumed, you can click on the card you see in the upper right corner to bring you to the relevant tutorial on that topic, in case you need a refresher. But if you are up to speed on the building blocks of life, it’s time to really begin to explore the diversity of living things, starting with plants. To be clear, botany involves much more than just understanding how plants harness energy from the Sun. Humans have been studying plants for as long as there have been humans. These studies have their roots, pun intended, in agriculture and herbalism, when our ancestors learned which plants were useful for nutritional and medicinal purposes.
It was only much later that the field grew to become what we now know of as botany, sometimes also referred to as phytology, when people became more interested in plant taxonomy, or the description of plant species and their classification into different groups of relatedness. So in studying botany today, you’re learning from a legacy of great scientists and explorers who were all fascinated by plants. In this series, we will learn about the parts of plants and how they grow. We will examine the different groups of plants, and get a sense of their evolutionary history. And we will learn about how plants interact with their environment. But in order to do all that, we need to start small. We need to start out by talking about cells, since like all other living things, plants are fundamentally composed of cells. We briefly discussed plant cells in the biology series, but it’s time to go deeper.