Nutrient cycles and human impact
18 review questions with answers for Nutrient cycles and human impact. Read them here, or play the set as a class game on the projector. Free to host, and students join with a code.
Process that removes carbon dioxide from the atmosphere?
- PhotosynthesisRight answer
- Respiration
- Combustion
- Decomposition
What this set covers
Cycling of carbon, nitrogen and water links to human impact in this set: photosynthesis, combustion, decay, nitrogen-fixing, nitrifying and denitrifying bacteria, methane, global warming, acid rain, eutrophication, bioaccumulation and biodiversity.
- Common mix-up
- Students often mix up nitrogen-fixing, nitrifying and denitrifying bacteria: they convert N₂ to ammonium compounds, ammonium to nitrate, and nitrate back to N₂ gas, in that order of the cycle.
- Review tip
- Draw the nitrogen cycle as a loop with the three bacterial types on the arrows, then trace one nitrogen atom from the air into a plant and back.
All 18 questions and answers
Process that removes carbon dioxide from the atmosphere?
Answer: Photosynthesis
Burning fossil fuels releases carbon dioxide by which process?
Answer: Combustion
Breakdown of dead organisms by microorganisms, returning nutrients to the soil?
Answer: Decay
Food keeps longer in a fridge because decay is slowed by conditions that are…?
Answer: Cold
Gas needed by most decomposers to break down material quickly?
Answer: Oxygen
Microbes in legume root nodules that convert N₂ gas into ammonium compounds?
Answer: Nitrogen-fixing bacteria
Soil microbes that convert ammonium ions into NO₃⁻ ions?
Answer: Nitrifying bacteria
Microbes in waterlogged soil that convert NO₃⁻ ions back into N₂ gas?
Answer: Denitrifying bacteria
Loss of water vapour from the leaves of plants?
Answer: Transpiration
Cooling of water vapour to form clouds?
Answer: Condensation
Greenhouse gas released in large amounts by cattle and rice paddies?
Answer: Methane
Rise in Earth's average temperature caused by extra greenhouse gases?
Answer: Global warming
Gas from burning coal that is a main cause of acid rain?
Answer: Sulfur dioxide
Algal growth from fertiliser run-off that leads to oxygen loss in lakes?
Answer: Eutrophication
Build-up of toxins, such as DDT, at higher concentrations in organisms further up a food chain?
Answer: Bioaccumulation
Large-scale clearing of trees, for example for cattle ranching?
Answer: Deforestation
Gas released when drained peat bogs are burned or left to decay in air?
Answer: Carbon dioxide
The variety of different species in an area?
Answer: Biodiversity
Play it as a class game
Play this set opens it in splycr, where you can host it for your class straight away. Hosting needs no account: put the room code on the projector, and students join from a phone with the code and their first name. Each question plays as multiple choice, and the three wrong options were written for that question.