Proterozoic

Home/Tag: Proterozoic
25 06, 2017

Where are the Rocky Mountains?

By |2018-04-21T11:56:41-07:00June 25th, 2017|Geology, North America|0 Comments

Rocky Mountains The Rocky Mountains stretch all the way from the southern United States north into Canada. They through Utah, Colorado, Wyoming, Montana, and up into Alberta. What we call the Rocky Mountains is really three different mountain chains, one on top of the other. The oldest mountain chain started more than a [...]

24 06, 2017

Proterozoic Eon – eukaryotes to worms

By |2018-04-21T11:56:39-07:00June 24th, 2017|Biology, Geology|0 Comments

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 [...]

2 06, 2017

Ice, water, and simple chemistry

By |2019-09-09T06:23:08-07:00June 2nd, 2017|Chemistry|0 Comments

Ice chemistry: Perito Moreno glacier, Argentina (thanks to Argentina's Travel Guide) How water freezes into ice When water gets colder than 32 degrees Fahrenheit or zero degrees Celsius, it freezes into ice. What is water made of? From water to steam More about temperature All our chemistry articles As the water gets colder, [...]

29 05, 2017

Mushrooms, biology and evolution

By |2017-05-29T16:56:04-07:00May 29th, 2017|Biology|0 Comments

Mushrooms growing in a field About 600 million years ago, a few eukaryote cells developed into multi-celled creatures. Some of them became animals, and some became plants, and others became mushrooms and the other funguses like yeast. So mushrooms are not either animals or plants. Mushrooms are actually more closely related to animals than [...]

29 05, 2017

Eggs – Evolution and Biology

By |2019-05-24T11:37:23-07:00May 29th, 2017|Biology|0 Comments

Fish eggs: Egg evolution starts with soft eggs like these When did the first eggs evolve? The earliest living creatures made babies by dividing themselves in half, so that one cell became two cells. But about 1.4 billion years ago, some creatures with more than one cell began to develop specialized cells. These [...]

29 05, 2017

What is RNA? Cell biology and evolution

By |2018-04-16T00:39:56-07:00May 29th, 2017|Biology|0 Comments

RNA molecule: A single strand of RNA, seen under an electron microscope The RNA molecule was probably one of the earliest steps towards life on Earth. RNA is short for "ribonucleic acid". That's a very long, complicated molecule made out of amino acids linked together. The amino acids are made out of atoms of [...]

29 05, 2017

Cell reproduction – Biology

By |2019-03-08T06:54:01-07:00May 29th, 2017|Biology|0 Comments

A cell dividing into two cells The first reproduction One of the main ways we define whether something is alive is whether it can reproduce - if it can make a new version of itself. The first things we know about that could reproduce were molecules of RNA, more than four billion years ago. What is [...]

29 05, 2017

What is photosynthesis? Plant Biology

By |2018-04-16T00:37:36-07:00May 29th, 2017|Biology|1 Comment

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. The first cells could not photosynthesize (foe-toe-SIN-the-size). They got food by breaking apart hydrocarbon molecules. But a little more than three billion years ago, [...]

29 05, 2017

What is a nucleus – Parts of a cell – Biology

By |2017-05-29T00:35:47-07:00May 29th, 2017|Biology|0 Comments

An onion skin cell (seen through a microscope) You can see the nucleus inside each cell The earliest cells, and all prokaryote cells, don't have a nucleus. Inside these simple cells, the DNA molecules just float around in the cytoplasm. This is a nice simple arrangement, but it's risky - the DNA often [...]

29 05, 2017

What are mitochondria? Parts of a cell – Biology

By |2017-05-29T00:26:07-07:00May 29th, 2017|Biology|0 Comments

A mitochondrion (seen through a microscope) About two billion years ago, in the Proterozoic, there were only prokaryotic cells on Earth. Mitochondria probably started out as independent cells that were especially good at digesting food. These cells were extra good at digesting because they had evolved to have two membranes. The inside membrane, [...]