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 [...]
Black-eyed Susan (the black in the middle is the seeds) - How flowers reproduce When did flowers evolve? The earliest flowers probably developed about 130 million years ago, in the [...]
A moss-covered rock During the Cambrian period, about 540 million years ago, some early plants evolved from earlier algae that could live on land, outside of the water. These plants [...]
A prokaryote (seen through a microscope) What does "prokaryote" mean? The simplest living cells are called prokaryotes, which is Greek for "before the nucleus" - these are cells that were [...]
Chloroplasts (seen through a microscope) Photosynthesis is the way some cells on Earth pull in light from the sun and use it to make energy to repair and reproduce themselves. [...]
A eukaryote cell (seen through a microscope) full of chloroplasts How do eukaryotes divide? Eukaryote cells generally reproduce themselves using a method called mitosis. When a eukaryote cell senses that there [...]
Fall leaves from a maple tree: their chloroplasts are dying off Why do leaves turn color? You can see that leaves are only green because of the chloroplasts, because in [...]
Chloroplasts (seen through a microscope) - how did chloroplasts evolve? When did chloroplasts evolve? The first cells that could make sugars out of sunlight and carbon dioxide and water by [...]
