biology

Home » biology

What are snakes? Evolution and biology

By |2018-04-15T00:32:41+00:00September 16th, 2017|Biology|

Two pythons Snakes evolved from lizards only about 150 million years ago, during the Jurassic Period. This is during the time of the dinosaurs, about the same time that the first birds evolved from small dinosaurs. Like birds and mammals, though, snakes really began to take over after most of the dinosaurs died about 95 million years ago, at [...]

The human body in medieval and modern science

By |2018-04-25T17:09:55+00:00September 6th, 2017|Biology, Science|

Chinese drawing of the organs (about 1200) Between the Middle Ages and modern times, doctors have learned a lot of new things about how human bodies work. The Islamic doctor Al-Tabari, in the early 800s, learned that light bounces off objects into your eyes. Al-Tabari's student Al Razi figured out that a fever is your body's way of fighting illness, not [...]

History of the human body – doctors and science

By |2018-04-25T17:08:36+00:00September 6th, 2017|Science|

Ebers Papyrus, one of the oldest known medical texts. From Egypt, about 1550 BC Doctors have been trying to figure out how the human body works since the Stone Age, and there are still many things we don't know about the human body even today. Medical researchers all over the world have contributed bits [...]

What is cholera? History of disease and medicine

By |2017-09-06T17:31:15+00:00September 6th, 2017|Biology, Science|

Washing clothes in the river (India) Cholera (KOLL-uh-rah) is a very serious sickness. It probably first got started in India. People in India were dying of cholera by the time of Chandragupta, about 300 BC, and maybe earlier. Cholera epidemics in India usually got started during monsoons. During the monsoon, warm rain fell and raised the water [...]

Who was Aristotle? – Greek philosophy – Ancient Greece

By |2018-05-11T14:11:12+00:00July 12th, 2017|Greeks, Philosophy|

Who was Aristotle? An ancient Egyptian papyrus with a scrap of Aristotle's "Politics" Aristotle's family Aristotle's father was Nicomachus, a doctor who lived near Macedon, in the north of Greece. (More about ancient Greek doctors) His mother Phaestis was from Euboea. She probably worked from home. So, unlike Socrates and Plato, Aristotle was [...]

Triassic period – pine trees and pterodactyls

By |2018-04-21T11:56:46+00:00June 25th, 2017|Biology, Geology|

A turtle in the desert During the Triassic period (about 248 to 199 million years ago), most of Earth's land continued to stick together in one big supercontinent, Pangaea. Because the middle of Pangaea was so far from the oceans, it was very dry there, like a desert. The whole world was generally [...]

Tertiary period – mammals and mountains

By |2018-08-22T05:19:59+00:00June 25th, 2017|Biology, Geology|

Tertiary period: Large animals evolved like moose Dinosaurs become extinct The Tertiary period begins with the catastrophe that killed off the dinosaurs at the end of the Cretaceous Period, about 65 million years ago. And the Tertiary lasts down to 1.8 million years ago. Mammals become more common With nearly all of the dinosaurs [...]

Silurian period – Fish get jaws

By |2018-04-19T11:29:11+00:00June 25th, 2017|Biology, Geology|

Silurian period: Trout swimming When was the Silurian period? The beginning of the Silurian period was about 443 million years ago. Some environmental problem at the end of the Ordovician period (probably ice ages) killed most of the plants and animals on Earth. The creatures that survived this extinction were the ones that [...]

Proterozoic Eon – eukaryotes to worms

By |2018-04-21T11:56:39+00:00June 24th, 2017|Biology, Geology|

Two and a half billion years ago, the Archaean Eon ended and the Proterozoic Eon began. Trillions of prokaryote cells lived in Earth's oceans. Some of these cells could photosynthesize their energy from sunlight, water, and carbon dioxide. These photosynthesizing cells pooped out a lot of oxygen. By about 2.3 billion years ago, the iron [...]

Digestion – Oxidation reaction – Chemistry

By |2017-06-03T00:41:56+00:00June 3rd, 2017|Biology, Chemistry|

Kids eating food (thanks to USDA) When animals, including people like you, digest their food, they use an oxidation reaction to break down big hydrocarbon molecules like sugar into different molecules. In order for your cells to break down sugar molecules made of hydrogen and carbon atoms, they have to combine the sugar with oxygen, just [...]