The mitochondrion is the powerhouse of the cell. Mitochondria and other organelles originated through a process of endosymbiosis: the eating of one cell by another. In this session, we’ll look at some of the evidence in support of this theory, including recent efforts to “engineer” new endosymbionts. The tree of life itself provides some experiments: many single-celled protists have “secondary” endosymbionts, acquired by eating a cell that ate a cell – hence "endosymbiosis+". At the end of this session, you will have a better understanding of endosymbiotic theory, a greater appreciation of the diversity of life at a cellular and organismal level, and some cool science stories to tell!

Can life survive on an alien world? The answer may be lurking on our own planet! In this course, we will learn about organisms that thrive in extreme environments: hot and cold, high salt, crushing pressure, and absolute darkness. These case studies illustrate a unifying principle of biology: life evolves biochemical solutions to match the challenges of the environment – past, present, and possibly future. As a part of this course, we will develop a working definition of life; learn how scientists use classic and modern “omics” techniques to study extremophiles and how to interpret the results; and design a plan for studying microbes in a new extreme environment.