Starter quiz
- Earth's atmosphere comprises approximately 21% of which gas?
- 'oxygen' ✓
- What is the percentage of carbon dioxide in Earth's atmosphere?
- 78%
- 21%
- 1%
- 0.04% ✓
-
- How old is Earth thought to be?
- 4 million years
- 4.5 billion years ✓
- 2 million years
- 200 billion years
-
- The atmosphere on Earth has been in roughly the same proportions for how many million years?
- '200' ✓
- What name is given to the layer of gas that surrounds a planet?
- 'atmosphere' ✓
What is the name of this process?- respiration
- combustion
- photosynthesis ✓
- sedimentation
-
Exit quiz
- Which of the following released gases forming Earth's early atmosphere?
- plants photosynthesising
- animals respiring
- volcanic activity ✓
- combustion of fuels
-
- What is the name of the process which uses energy from sunlight to convert carbon dioxide and water into glucose and oxygen?
- 'photosynthesis' ✓
- Which was the most abundant gas in the early atmosphere?
- nitrogen
- oxygen
- argon
- carbon dioxide ✓
-
- Algae evolving led to increased levels of which gas in the atmosphere?
- 'oxygen' ✓
- Put the statements into the correct order to describe how the oceans formed.
- 1⇔Volcanic activity released water vapour into the atmosphere.
- 2⇔The surface temperature of Earth cooled.
- 3⇔As the surface temperature reached 100℃ water vapour condensed.
- 4⇔Liquid water fell to Earth forming the oceans.
- Which of the following led to decreased levels of carbon dioxide in the atmosphere?
- respiration by animals
- carbon dioxide dissolving in the oceans ✓
- algae and plants photosynthesising ✓
- carbon being 'locked up' in sedimentary rocks and fossil fuels ✓
- combustion of fuels
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Worksheet
Presentation
Video
Lesson Details
Key learning points
- Early volcanic activity is thought to have made an atmosphere of carbon dioxide and nitrogen billions of years ago.
- Carbon dioxide can dissolve in oceans and form carbonates which, over millions of years, can form sedimentary rock.
- The amount of carbon dioxide was reduced by the formation of sedimentary rocks and photosynthesis by algae and plants.
- Algae and plants produced the oxygen that is now in the atmosphere by photosynthesis.
- Phytoplankton in the oceans are responsible for roughly half of all oxygen production that takes place today.
Common misconception
The Earth's atmosphere has always contained oxygen. The atmosphere's composition is static and unchanging.
Clarify the development of oxygen through photosynthesis. Describe how atmospheric composition has evolved over time due to geological and biological processes.
Keywords
Volcano - A volcano is an opening on the surface of a planet or moon through which molten rock, rock fragments and gases erupt.
Sedimentary rock - Sedimentary rocks are a type of rock formed from the compression of sediments (rock fragments, minerals and remains of dead plants and animals).
Photosynthesis - The process of photosynthesis is where energy from sunlight is used to convert carbon dioxide and water into glucose and oxygen.
Algae - Algae are a diverse range of unicellular or multicellular photosynthetic organisms. Many algae are aquatic.
Phytoplankton - Some types of algae belong to a group of microscopic marine photosynthetic organisms called phytoplankton.