Energy, food and agriculture.
Question:
Will it be possible, maybe with the help of scientific
advances, for the earth to support 10 billion
people? Explain your answer.
Will it be possible, maybe with the help of scientific advances, for the earth to support 20 billion people?
Explain your answer.
In terms of energy humans need for living, what would be the limiting factor in human population growth?
The Agricultural Revolution
https://www.youtube.com/watch?v=bhzQFIZuNFY
In which areas of the world did people first learn agriculture?
In what ways did the agricultural revolution shape our world today ( and over the last 10,000 years )?
Give 5 examples.
Do some research! Find data which gives human population density in an area such as Eastern China where
intensive agriculture was practiced, compared to for example pre- European Australia where the lifestyle was
more hunter-gatherer.
The Nitrogen Cycle
https://www.youtube.com/watch?v=leHyY_8nRs
Why is nitrogen such an important element
in helping plants grow?
The atmosphere is around 80% pure
nitrogen. Isn’t that plenty to support plant
life and farming?
How have humans traditionally added nitrogen and other nutrients to the soil?
Why do fertilizers need to be soluble in water? What forms of water nitrogen are commonly found in the
What is the “Haber process” and why is it sometimes called the most important industrial chemical process?
Write a chemical equation for the formation of ammonia in the Haber process.
Powerpoint Slide show illustrating the Nitrogen cycle.
https://www.slideshare.net/cpodjames/nitrogen-cycle-powerpoint-2001301
Define the following terms:
Nitrogen fixation
Nitrification
Nitrogen-fixing bacteria
Nitrifying bacteria
Denitrifying bacteria
Answer the following questions:
1. What is the role of plants in the nitrogen cycle? In what form of nitrogen do plants interact.
2. Discuss the importance of bacteria in the nitrogen cycle?
3. What is the role of decomposers in the nitrogen cycle?
Final BIG Questions:
( these are not political questions, they are social and scientific!)
Why might it be said that the human diet should be a vegetarian one? Give some scientific and some cultural
benefits and drawbacks.
Why do you think population growth in many European countries is slowing or even declining, whilst in many
other parts of the world it is accelerating?
China’s One Child policy was implemented as a solution to overpopulation but its was unpopular with many
people. What were some of the benefits and some of the drawbacks to the policy?
Why do you think the policy is no longer continued?
Warm up questions: ( from the formative quiz)
What is the source of all the energy stored in the food you eat?
Name the process by which that energy is trapped.
In what form is the energy stored in food?
What is a Producer in terms of food energy?
What is meant by the phrase trophic level?
What is the difference between a food chain and a food web?
As energy is passed on when one organism eats another, about how much energy actually gets from one level
to the next?