Human organs: medieval science
Chinese drawing of the human organs (about 1200) Eyes and fevers Between the Middle Ages and modern times, doctors have learned a lot of new things about how human bodies [...]
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09, 2017
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09, 2017
Medicine and doctors in the Roman Empire
Roman medicine: Galen used surgical instruments like these What do we mean by Roman medicine? Roman medicine is really West Asian and African medicine. That's because most of the great [...]
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08, 2017
What is electricity? Physics
What is electricity? A bolt of lightning in the sky What is electricity made of? Everything in the universe is made of atoms. Those atoms are made of electricity. Atoms are [...]
27
05, 2017
Why do eyes have pupils?
Cats have pupils that can get bigger or smaller. Eyes start to focus light By around 550 million years ago, some kinds of worms evolved eyespots sunk into their heads to protect [...]
27
05, 2017
What are neurons? Nervous system evolution and biology
A network of neurons One-celled creatures like bacteria don't have neurons, because they can communicate within themselves through the use of enzymes, but all multicellular animals do have neurons. The [...]
27
05, 2017
How did nerves and brains evolve? Biology and Evolution
The yellow string is one of the arm nerves of a cat By around two billion years ago, some eukaryote cells were able to sense changes in their surroundings and [...]
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05, 2017
What is a brain? Biology and Evolution
This is a mouse brain When did the first brains evolve? Flatworms were the first animals to evolve anything like a brain, but it's really just a thickened part of [...]
