SAQs
Now that you have completed this study session, you can assess how well you have achieved its Learning Outcomes by answering these questions.
Rewrite the paragraph below using terms from the list provided to fill the gaps.
age dependency ratio, demographic transition, population composition, population pyramid, sex ratio.
Populations change over time as birth and death rates vary in a process called ……………… At any one time, the characteristics of the population of a country are described by its ……………… One of the factors typically included is the ………………, which compares the numbers of men and women. The other important ratio is the ……………… These two main population characteristics can be presented as a ………………
Populations change over time as birth and death rates vary in a process called demographic transition. At any one time, the characteristics of the population of a country are described by its population composition. One of the factors typically included is the sex ratio, which compares the numbers of men and women. The other important ratio is the age dependency ratio. These two main population characteristics can be presented as a population pyramid.
Which of the following statements are false? In each case explain why it is incorrect.
- Advances in agricultural science and technology lead to changes in death rates.
- Falling birth and death rates are characteristic of stage 1 of demographic transition.
- Advances in public health measures are reducing the death rate.
- Processes for food production and distribution are the same throughout the world.
- The total population of a country increases to a maximum in stages 4 and 5 of demographic transition.
2 is false. Falling birth and death rates are characteristic of stages 2 and 3, not stage 1.
4 is also false. Processes for food production and distribution are not the same throughout the world; food production systems are generally more advanced in developed than in developing countries.
Which of the following statements are false? In each case explain why it is incorrect.
- Developing countries have old populations, while developed countries have young populations.
- Sex ratios may vary due to different patterns of death and migration for males and females within the population. For example, males are more likely to migrate or to be killed in wars; both these factors would decrease the sex ratio within a population.
- The age dependency ratio can be used as an indicator of the economic burden of a country.
- The shape of the population pyramid of a country with a high age dependency ratio is always broader at the bottom than the top.
1 is false. Developing countries have young populations while developed countries have old populations.
4 is false. If the shape of the population pyramid is broader at the bottom this indicates a large number of young children; however, the age dependency ratio also depends on the number of people aged over 65.
Briefly explain the relationship between population growth, food security and health.
Population growth means that more people will require sufficient food to meet their dietary needs. Food security can be improved by increasing the quantity of food produced by changing agricultural practices such as use of fertilisers or growing different crops. However, any improvements to agricultural productivity have to match the rate of population growth if they are to make a difference to food security. Long-term malnutrition makes people more vulnerable to disease and causes stunting, which impairs child development.
You are putting together a presentation on interactions between poverty and the environment for a class of high school students. List five points you plan to address in your presentation.
In your presentation you should have covered five of the following points:
- Poor people are more directly dependent on the environment for their food, water, fuel and medicines.
- The environment is the source of income for many poor people through sectors such as agriculture, forestry, fishery and tourism.
- Environmental problems such as flood and drought tend to have a bigger impact on poor people.
- As environment influences poverty, poverty also affects the environment. For example, cutting down trees for fuel leads to deforestation and soil erosion.
- Poor farmers tend to lack the education, resources and security in land ownership to invest in environmentally friendly technologies.
- Poverty leads to environmental degradation which reduces agricultural productivity and makes poor people poorer in a downward spiral.