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Central dogma (DNA to RNA to protein)

How does a gene in your DNA provide instructions for building a protein? In gene expression, a DNA sequence is first copied to make an RNA molecule, which is then "decoded" to...

Khan Academy

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Gene regulation

You have tens of thousands of genes in your genome. Does that mean your cells express all of those genes, all the time? Not by a long shot! Even an organism as simple as a...

Khan Academy

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Biotechnology

What is biotechnology? Well, if you've ever taken the antibiotic penicillin or eaten bread made with yeast, you've experienced it firsthand! Biotechnology is the use of a living...

Khan Academy

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Developmental biology

Did you know that a frog starts out as a single cell? In fact, so do dogs, elephants, and even human beings! Learn how multicellular organisms end up with many different cell...

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Bacteria and archaea

They're everywhere. They number in the millions of trillions of trillions. They live on every surface, in every environment, and even in your gut. That's right...I'm talking about...

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Viruses

Viruses: Are they alive? Are they dead? Are they...undead? Learn more about these fascinating (and clinically important) particles that occupy a "gray area" between living and...

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Ecology

Why are polar bears found only in the Arctic? Why does mildew grow in your shower and not (hopefully) in your sock drawer? Learn how ecologists study the interactions between...

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Biodiversity and conservation

From penguins to palm trees to bacteria, our planet is host to an awe-inspiring diversity of organisms. Dive deep into Earth's breathtaking biodiversity, learn why this...

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Behavioral biology

What do a dog begging for food, and ant leaving a chemical trail to food, and a human baby learning language all have in common? These are all examples of behaviors. Behavior is a...

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Principles of physiology

How is your body organized? How do your organ systems work together to keep you running? What keeps your blood at the right pH or your body at the right temperature? Learn more...

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