Continuing on from the previous episode, I discuss the role of antibodies and antigens in mediating adaptive immunity, and follow with a discussion of the functions and roles of B-cells and T-cells. I conclude the episode with an overview of the many components of the immune system and a discussion of how they interact to protect the body from pathogens. Recommended prelistening is Episode 72: Introduction to the Immune System Part I.

An overview of the human immune system, beginning with some basic anatomy of the lymphatic system, and proceeding through a discussion of the distinction between the innate and adaptive immune systems, the role of skin and mucus membranes in providing barriers to pathogen entry, the inflammatory response, an overview of the different types of leukocytes, and an initial foray into the workings of the complement system. Recommended pre-listening is Episode 10: The Cell.

A social scientific discussion and comparison of some of the major political ideologies in the world today, beginning with an overview of the origins, meaning, and limitations of the 'left-right' political spectrum, and continuing with an analysis of the historical origin and key beliefs of conservatism, liberalism, socialism, communism, anarchism, fascism, and other nationalist movements.

Continuing from Episode 69, I explore the diversity of the mammals, looking at all the mammalian orders and their major families. Special focus is given to primates and particularly hominids, which are discussed at the species level.

In this episode we explore the diversity of the animal kingdom. I first discuss the history of taxonomy and give an overview of some key concepts such as morphological similarity, phylogenetic analysis, systematics, cladistics, binomial classification, and the taxonomic hierarchy. Then follows an explanation of the diversity of and relationships between the major animal phyla, including arthropods, echinoderms, molluscs, and many others, with special emphasis is given to the classes and orders in the phylum of chordata (vertebrates).

An overview of the structure and function of proteins. Beginning with a discussion of some key research methods for studying proteins, including column chromatography, electrophoresis, and x-ray crystallography, we then discuss the structure of proteins, with a focus on secondary structure, motifs, structural domains, and quaternary structure. The episode concludes with a look at protein function, including protein folding, denaturation, enzymatic function, and allosteric regulation. Recommended pre-requisites are Episode 18: Biochemistry Basics, and Episode 10: The Cell. Episode 32: Light and Optics may also be helpful for the crystallography portion.

Concluding the brief exploration of language begun last time, this episode examines semantics, including the distinction between sense and reference and different types of utterances, pragmatics, including conversational maxims and implicatures, and sociolinguistics, including prestige dialects and speech acts. Recommended pre-listening is Episode 66: An Overview of Language Part 1.

In this first of a two-part episode, I discuss the phenomenon of language. Here we consider phonetics, how sounds are produced and articulated, phonology, how different sounds are distinguished from one another and treated across different languages, morphology, how sounds are combined into units of meaning called morphemes, and in turn how these are combined into words, and syntax, how words are put together in accordance with particular rules to form sentences.

An introduction to the concept of money, including its uses, purpose, and a brief account of its history. I discuss the notion of money as a medium of exchange, a unit of account, and a store of value, and some of the properties that make particular goods useful as money. I also discuss various measures of the money supply, and briefly outline the difference between the monetary base and money created through the fractional reserve system. I discuss inflation, including its definition, causes, and effects on the economy, before concluding with a brief look at interest rates and exchange rates.