This question is about the cycling of water and carbon in ecosystems - AQA - GCSE Biology Combined Science - Question 1 - 2022 - Paper 2
Question 1
This question is about the cycling of water and carbon in ecosystems.
Which reaction produces water?
Tick (✓) one box.
Aerobic respiration
Anaerobic respiratio... show full transcript
Worked Solution & Example Answer:This question is about the cycling of water and carbon in ecosystems - AQA - GCSE Biology Combined Science - Question 1 - 2022 - Paper 2
Step 1
Which reaction produces water?
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The reaction that produces water is aerobic respiration. This reaction occurs when glucose is broken down in the presence of oxygen, releasing energy, carbon dioxide, and water as byproducts.
Step 2
Name the processes 1 to 5 shown on Figure 1.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Evaporation
Condensation
Precipitation
Drainage
Transpiration
Step 3
Calculate how many people had severe water shortage.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To find the number of people with severe water shortage, first calculate 4.5% of the world population:
6,000,000,000 imes rac{4.5}{100} = 270,000,000
Thus, the number of people who had severe water shortage is 2.7×108.
Step 4
Why do more people have severe water shortage now than in 2007?
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Climate change has increased the area of deserts.
More water is used to grow crops.
Step 5
Explain how microorganisms recycle carbon from the leaves.
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Microorganisms in the soil decompose fallen leaves, breaking them down into simpler organic and inorganic materials. During this process, they release carbon dioxide back into the soil, which can then be utilized by plants for photosynthesis, promoting new plant growth.
Step 6
What is one benefit of fallen leaves for living plants?
97%
121 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
One benefit of fallen leaves for living plants is that nitrates are released into the soil. This enhances soil fertility, providing essential nutrients for plant growth.