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Can the Earth Cope?. HOW DO POPULATIONS CHANGE?. Starter 1. What do you think this cartoon is trying to show? . OBJECTIVES: To understand that the earth’s population is increasing and to be able to explain why. To define birth rate, death rate and natural increase
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HOW DO POPULATIONS CHANGE? KCo
Starter 1 What do you think this cartoon is trying to show? KCo
OBJECTIVES: • To understand that the earth’s population is increasing and to be able to explain why. • To define birth rate, death rate and natural increase • To identify factors that affect population change KCo
What is the population of the world? Jot down your answer in the back of your book How accurate were you? World Population clock Weblink www.odci.gov/cia/publications/factbook KCo
Skills task: • How would you describe this graph showing world population growth? • State the trend/ pattern (increase/ decrease/remains steady) • Highest and lowest figures • Quote figures to support key ideas At present the world's population is growing quickly, though this has not always been the case. • Until the 1800s the world's population grew slowly for thousands of years. • In 1820 the world's population reached one billion. • In the early 1970s, the world's population reached three billion. • In 1999, less than 30 years later, the population doubled to six billion (population explosion) • The global rate of population growth is now one billion every 15 years. • The graph shows this pattern of accelerating growth (including the predicted population for 2025). KCo
What does this graph suggest about the growth in the world population? What are developed and developing countries? Why do you think there is such a difference between them in terms of population growth? KCo
Population change depends mainly upon the balance between: • Birth rate • Death rate • Migration • Birth rate- the number of live babies born in a year for every 1000 people in the total population, e.g. 25/1000 • Death rate- the number of deaths each year per 1000 people in the total population • Natural increase- the difference between the birth rate and death rate Birth rate – death rate = natural increase Record these key terms and equations in your exercise book. KCo
THE POPULATION CLOCK How many births are there in 5 seconds?. How many deaths are there in 5 minutes? By how much does the population change in 2 days? World Population Clock KCo
Activity Can you think of some times and numbers that you are familiar with? Use your times and the figures from the previous table to describe 2ideas. e.g. It takes me 13 seconds to run 100 metres. In that time there would be an extra 53 births. KCo
Activity Copy and complete the table above using the notes you made earlier to help you with equations. What do you notice about the countries? KCo
Extension Watch the newsbite about the world’s population reaching 7 billion people Watch the BBC clip about the world population reaching 7 billion people and what is predicted for the future. http://www.bbc.co.uk/news/world-15445092 KCo
Activities Connections pages 90-91 new edition (70-71 old edition). Complete the ‘extras’ activities. KCo
Population growth has not been even throughout the world. The fastest growth has been in the poorer, less economically developed countries. There is very slow growth in the richer, more economically developed countries. • Why do LEDCs have higher birth rates? • Why do MEDCs have lower death rates? KCo
PLENARY • With so many people on the planet what problems could we face? KCo
Homework Population Change Investigation Use the BBC website to investigate population change and complete the questions on the sheet KCo