Recycling Flashcards
What are the main things that we can recycle?
- glass
- metal
- paper
- plastic.
How is glass recycled?
It can be melted and remoulded to make new objects, such as bottles. The energy needed to do this is less than the energy needed to make new glass from its raw materials
How is metal recycled?
Metals can also be melted and remoulded to make new objects. Aluminium is a valuable metal that melts at a relatively low temperature, and is particularly attractive for recycling.
How is paper recycled?
Paper is not melted when it is recycled. Instead, it is broken up into small pieces and reformed to make new sheets of paper.
How is plastic recycled?
Plastic can be recycled as fleece clothing so that we use less crude oil, the raw material required for plastic and a scarce resource that is running out.
Describe the carbon cycle
Plants absorb CO2 from the environment which enables their cells to produce sugars by photosynthesis. When plants are eaten by animals, the carbon in the plant tissues become party of the animal bodies. This transfer of carbon continues as animals are eaten by animals. During respiration, organisms release carbon dioxide into the atmosphere. It is also released by the burning of fossil fuels. Chalk is formed from the fossilised remains of sea creatures. Exposed to rain, the chalk dissolves and more carbon dioxide is released.
What is nitrogen essential for?
Nitrogen is essential for the formation of amino acids in proteins.
What are the steps of the nitrogen cycle?
- Nitrogen gas is converted to nitrate compounds by nitrogen-fixing bacteria in soil or root nodules. 2. Lightning also converts nitrogen gas to nitrate compounds. The Haber process converts nitrogen gas into ammonia used in fertilizers. Ammonia is converted to nitrates by nitrifying bacteria in the soil.
- Plants absorb nitrates from the soil and use these to build up proteins. The plant may be eaten by an animal, and its biomass used to produce animal protein.
- Urea and egested material is broken down by decomposers. This results in nitrogen being returned to the soil as ammonia.
- Decomposers also break down the bodies of dead organisms resulting in nitrogen being returned to the soil as ammonia.
- In some conditions denitrifying bacteria in the soil break down nitrates and return nitrogen to the air. 7. This is usually in waterlogged soil. Improving drainage reduces this effect, making the soil more fertile.
Which microorganism turns nitrogen gas into ammonia?
Nitrogen fixing bacteria.
Which microorganisms convert nitrates to nitrites?
Denitrifying bacteria convert nitrates into nitrites.
Which microorganism turns ammonia into nitrates?
Nitrifying bacteria convert ammonia into nitrates.
What is the name of the soil bacteria that convert proteins and urea into ammonia?
Decomposers.
