 Hello everyone and welcome to Biology 305, otherwise known as genetics. The purpose of this course is to give you an overview of the field of genetics. We'll talk about where the field has been, what's been discovered, and a brief bit about what might be to come. For every unit that we cover in this course, we will have an introductory lecture. The purpose of this lecture is to orient you and give you a glimpse as far as what information we will cover. You'll also have a series of mini lectures. The mini lectures are meant to give you either supplementary material to help fill in some of the blanks, make some connections, or to give you some extra material when things start to get difficult. For example, at the end of this introduction, you'll have a brief additional lecture that will briefly discuss the genetics timeline. You'll have a second mini lecture at subunit 1.2, which we'll talk about Mendelian genetics. You'll have another mini lecture at subunit 1.3 covering the Punnett square, at 1.7 covering probability, and finally at 1.8 covering pedigrees. Genetics is the study of heredity, genes, and variation. The word genetics means origin, and it came from ancient Greece. The exact beginning of the field of genetics is hard to pinpoint, but the first documented records of the study of heredity began with Gregor Mendel in the mid-1800s. We will focus on Mendel in depth in the next lecture, but for right now, we just ask that you remember he is credited with being the father of genetics. Since Mendel's time, the field of genetics has blossomed into many different sub-disciplines. Current research focuses on things including medical genetics, which looks at the diagnosis and management of genetic disorders, evolutionary genetics, which looks at changing gene frequencies through time, gene regulation, which looks at how genes are turned on and off, genetic counseling, which looks at the inheritance of genetic disease in families, gene expression, which looks at information in a gene and how it's used to synthesize a product, and then, of course, developmental genetics, which looks at how genes are turned on and off as a zygote or embryo develops into an adult. And this is just to name a few. The first few subunits, subunits 1.1, 1.2, and 1.3, are designed to give you a historical perspective to the field of genetics. If you don't know the history of a field, it's difficult to understand how it progresses and where it may go in the future. Subunit 1.1 will focus on the long-term history of genetic study. We will provide you with two timelines that will show you where the recorded field of genetics began, how it has progressed over time, and even where it stands today. Subunit 1.2 will focus on Mendel, his work and what he found, and then how a mild-mannered friar from Austria managed to change the field of science forever. Subunit 1.3 will focus on a basic genetics tool called the punent square. The punent square was created by an English geneticist named Reginald Punnett in the early 20th century. This tool has been used for teaching ever since, and it's very effective in demonstrating genetic principles that Mendel discovered. Given what we have discussed, it's time to come up with your own definition of genetics. So how would you define genetics? Take a minute, pause this lecture, and give your own definition of this field. The other concepts we would like you to think about is how the field of genetics impacts you every day. Well, one example is, have you ever thought to yourself, why do I have my mom's hair? Or why do I have my dad's laugh? Better yet, when you were young, did you say to yourself, I am nothing like my parents. I am never going to do that. Only to find yourself doing whatever that is years later? Chances are there's a genetic basis for this, and the reason that you are who you are, and you do the things you do, have strong genetic underpinnings. Now, that doesn't mean you can blame everything on your parents, but there is a genetic reason for your biological features and behaviors. As we go through the course, we hope you enjoy the material we present. Chances are you will learn many things that are very applicable to your everyday life. Chances are you will learn many things that are very applicable to your everyday life.