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Planet : The Great Oxidation Event

Author - Kirsten Noome Illustration - Kirsten Noome, kirsten Noome, Pixa Bay, SVG Sihl, Cyano Biotech, Welcome To Fanaru and Science For Kids Language - English Level - Longer paragraphs © Kirsten Noome Creative Commons: Attribution 4.0 Source www.africanstorybook.org

Planet Earth: The Great Oxidation Event Kirsten Noome Kirsten Noome

English

Even though the Earth froze over, The book has 8 riddles to solve! there was still that managed to survive. After the came Cy the cyanobacteria and Oxy the plants, fish and then the first four molecule are ready to take legged animals. The Earth had 5 you on a trip back in time to the Great major after the Great Oxidation Event. Oxidation Event and yet Earth continued until where we are today. Cy will help you learn interesting new facts about the world and Oxy is there What do you think the future of the to give you the definitions to new planet will hold? words.

20 1 Most of me is water but some of me is Answer: . land Organisms that couldn't survive in the I am third from the sun new oxygen environment became extinct. Others managed to live in I weigh more than a tonne and places with less oxygen. The high amount of oxygen in the atmosphere of the planets with life, I am the only reduced the levels. This one caused a called the . What am I?

2 19 If you lived on Earth Answer: the planet Earth.

But your species won't continue Earth is the third planet in our solar system. The Sun and its family of You are likely on a path planets (Mercury, Mars, Earth, Venus, Jupiter, Saturn, Neptune and Uranus) That the dodo followed too formed when a cloud of dust and gas condensed 4.6 billion years ago. What am I?

18 3 I am a blanket but Proof of this is found today in banded formations. You cannot use me

I make the weather for the planet,

And I'm held in place by gravity

What am I?

4 17 Evidence of the Great Oxidation Event: Answer: the atmosphere.

The amount of oxygen in the Volcanoes coughed gases into the air. atmosphere grew and grew. This These gases were kept high in the air changed the world from anoxic to oxic by the Earth's gravity. This formed the conditions. This event is sometimes early atmosphere. It was made up of called the Oxygen Catastrophe methane, ammonia, neon, water because it caused the extinction of vapour and , and dust anaerobic organisms. from meteors passing through the atmosphere. There was little or no free oxygen in the early atmosphere.

16 5 I wave but Answer: the process of oxidisation.

I have no hand After cyanobacteria had introduced oxygen into the ocean, the oxygen I cover a lot of the planet reacted with the dissolved iron. This means that oxygen stole electrons But I am not land from iron. While oxygen gathered electrons, the iron became oxidised. What am I? This created green rust in the ocean.

6 15 I am a process of reaction Answer: the ocean.

Oxygen stole electrons from Fe, Water vapour arrived in the atmosphere from ice in comets and It was this interaction gases that escaped the Earth's molten . After the Earth cooled down, the that made water rusty water vapour formed clouds. The clouds condensed and it rained for What am I? many centuries, filling up all the hollow basins in the Earth's surface, forming the early ocean.

14 7 Some call me a catastrophe Answer: oxygen.

Free oxygen in the atmosphere was Oxygen is a tasteless, colourless, my birth odourless gas. The periodic table sorts the gases into a table, oxygen Written in my biography has the atomic number 8. Oxygen is the air that we breathe, without it Is a mass extinction on the Earth there would be no aerobic organisms on Earth. What am I?

8 13 I replenish the Earth's atmosphere Answer: the Great Oxidation Event (GOE). And I am the atomic gas number eight The GOE was the introduction of free oxygen into the atmosphere 2.4 billion You won't find me higher than the years ago. This was because stratosphere cyanobacteria and made oxygen as waste. Oxygen Trees excrete me when they reacted with dissolved iron in the metabolite ocean through oxidisation.

What am I?

12 9 I belong to the phylum bacteria Answer: cyanobacteria.

I get my food through Cyanobacteria first appeared around 2.7 billion years ago in the Archaean The ocean is my utopia era. They are also called blue-green algae. They can use photosynthesis to And without me the Earth would be make food and release free oxygen as lifeless a waste product.

What am I?

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