So maybe we can't outrun cheetahs or antelope, but humans are uniquely adapted for long distance running. What does science have to say about marathon running? To find out, (and because I was feeling a little crazy) I decided to run one!...

Your brain does its best to inform you about the world around you, but sometimes it gets tricked. Enjoy eight optical illusions to test your brain's sensory input.

In this video Paul Andersen explains the importance of oxygen in accepting electrons. He begins with a brief description of combustion. He then explains the role of oxygen in aerobic cellular respiration.

It's time to have a look at the future of human life and how technology could possibly extend longevity. But, within that tech, are questions of ethics that are not always at the top of mind when the tech is being developed. In this...

After World War Two, the applications of basic discoveries in biology took off—and became big business. Today, we’ll look at the rise of Big Pharma and GMO foods. We’ll also discuss how life-science technologies fundamentally changed...

It's all about the SUPER TINY in this episode of Crash Course: History of Science. In it, Hank Green talks about germ theory, John Snow (the other one), pasteurization, and why following our senses isn't always the worst idea.

Paul Andersen explains how organs work together to form organ systems and how organ systems work together to form organisms. The kidney and bladder work together to filter blood in the excretory system. The circulatory and respiratory...

Paul Andersen differentiates between biotic and abiotic factors. He explains how both abiotic and biotic factors can affect organisms at the level of the cell, the population and even the ecosystem. The complexities of biofilms,...

Paul Andersen surveys the circulatory system in humans. He begins with a short discussion of open and closed circulatory systems and 2,3, and 4-chambered hearts. He describes the movement of blood through the human heart and the blood...

We've harnessed electricity, sequenced the human genome, and eradicated smallpox. But after billions of dollars in research, we haven't found a solution for a disease that affects more than 14 million people and their families at any...

This week on SciShow news, strap in for a trip through the frontier of the human brain. The human connectome is a years long venture to explore and map the pathways of the human brain, and this past week scientists released two terabytes...

It's time to start talking about some of the terrible things you can do to your own body, like blood doping. We'll start by explaining the structure and function of your erythrocytes, and of hemoglobin, which they use to carry...

Now that we've talked about your blood vessels, we're going to zoom in a little closer and talk about your blood itself. We'll start by outlining the basic components of blood -- including erythrocytes, leukocytes, platelets, and plasma...

We're kicking off our exploration of muscles with a look at the complex and important relationship between actin and myosin. Your smooth, cardiac, and skeletal muscles create movement by contracting and releasing in a process...

For most of us, our bodies are interacting with phones nearly all the time, whether we're looking at screens, listening to music, or carrying them in our pockets. If you are wondering about the health implications of a world filled with...

Paul Andersen previews the information in the genetics unit. He defines the central dogma of biology and explains how DNA creates an RNA transcript that is used to translate proteins. He differentiates between mitosis and meiosis. He...

Settle in for a smörgåsbord of brain facts.

Today Hank explains the skeletal system and why astronauts Scott Kelly and Mikhail Kornienko are out in space studying it. He talks about the anatomy of the skeletal system, including the flat, short, and irregular bones, and...

Paul Andersen compares and contrasts mitosis and meiosis. He shows how you can count cells in various phases of mitosis to construct a cell cycle pie chart. He also explains how you can use the fungus Sordaria to calculate map units...

In this video Paul Andersen explains the importance of mitosis and details the major steps in the cell cycle. He explains the importance of Interphase, Prophase, Prometaphase, Metaphase, Anaphase, Telophases, and Cytokinesis.

Imagine something small enough to float on a particle of dust that holds the keys to understanding cancer, virology, and genetics. Luckily for us, such a thing exists in the form of trillions upon trillions of human, lab-grown cells...

Today we’re going to talk about ethical data collection. From the Tuskegee syphilis experiments and Henrietta Lacks’ HeLa cells to the horrifying experiments performed at Nazi concentration camps, many strides have been made from...

Paul Andersen explains how the central dogma of biology explains life on our planet. He starts with a brief discussion of common characteristics of all life. He then explains how DNA is used to make proteins which in turn make you. He...

Paul Andersen explains how DNA replication ensures that each cell formed during the cell cycle has an exact copy of the DNA. He describes the Meselson-Stahl experiment and how it showed that DNA copies itself through a semi-conservative...