AQA GCSE Biology (8461), Higher tier · Ecology › Biodiversity and human interaction
Practise Global warming. 11 exam-style questions plus unlimited generated ones on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy5 marks
The levels of some gases in the atmosphere are increasing and contributing to global warming.
(a) Which two gases contribute to global warming? Tick (✓) two boxes.[2]
Carbon dioxide
Methane
Nitrogen
Oxygen
(b) Give one human activity that increases the level of methane in the atmosphere.[1]
(c) Give two biological consequences of global warming.[2]
Show the answer and mark scheme
(a)Answer: Carbon dioxide; Methane
(b)
cattle farming
growing rice in flooded fields
landfill / anaerobic decay of waste
extracting fossil fuels (leaks of natural gas)
(c)
loss of habitat, e.g. low-lying land flooded as sea levels rise
changes in the distribution of species
changes in migration patterns
reduced biodiversity / extinction of species
pests and diseases spread to new areas
changes in crop yields / in where crops can be grown
Question 2Medium7 marks
Scientists recorded the day of the year on which frogs in one area first laid eggs (spawn), and the mean temperature in February. {table} shows the results. Day 1 is 1 January.
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(a) Describe the relationship between the mean February temperature and the day on which first spawn was seen.[1]
(b) Calculate the mean number of days per year by which spawning became earlier between 1990 and 2020.[2]
(c) Suggest two reasons why spawning earlier could be a problem for frogs.[2]
(d) Scientists use data like these as evidence of the effects of global warming. Explain why records from many species in many different places are more convincing than records from one species in one place.[2]
Show the answer and mark scheme
(a)
the higher the temperature, the earlier the frogs spawn / negative correlation
(b)Answer: 0.9 days per year
(72 − 45) ÷ 30
0.9 (days per year)
(c)
a late frost could kill the eggs / tadpoles
the tadpoles may hatch before there is enough food (e.g. algae) for them
the pond may be too cold for tadpoles to develop well
(d)
one species in one place could be affected by local factors, e.g. local weather or habitat changes
if many species in many places show the same trend, it is more likely to be caused by a widespread change in climate
Question 3Hard6 marks
Scientists predict that the mean temperature of the Earth will continue to rise.
Describe and explain some of the biological consequences of global warming.[6]
Show the answer and mark scheme
sea levels rise (ice melts and water expands), flooding low-lying habitats such as salt marshes and islands, so species lose their habitat
species move towards the poles or to higher altitudes as temperatures rise, so their distribution changes
species that cannot move, e.g. those on mountain tops or islands, may become extinct
the timing of seasonal events changes, e.g. animals migrate earlier or later, or change their migration routes
animals may breed at the wrong time for their food supply, so fewer young survive
biodiversity may fall as some species become extinct
pests and insects that carry diseases spread to new areas
crop yields change and the places where crops can be grown change, which affects food security
Marked with levels of response: the full level descriptors are in the app.