Population Pyramids

Question 1

What is a population pyramid?

Answer 1

• a bar graph that shows the composition, by age and sex, of a nation’s population at the time of a census

Question 2

What are the main age/sex groups that a population contains?

Answer 2

• pre-reproductive
• reproductive
• post-reproductive

Question 3

What is age structure?

Answer 3

• the relative numbers of individuals of each age in a population

Question 4

What do the different population pyramid shapes depict?

Answer 4

• a rapidly growing population
• a stable population
• declining population

Question 5

What are the characteristics of a rapidly growing population pyramid?

Answer 5

• high birth rate
• rapid fall in each upward age group due to high death rates
• short life expectancy
• commonly found in LDCs

Question 6

What are the characteristics of a stable population pyramid?

Answer 6

• declining birth rate
• low death rate
• more people living due to old age
• found in MCDs

Question 7

What are the characteristics of a declining population pyramid?

Answer 7

• low birth rate
• low death rate
• higher dependency ratio
• longer life expectancy as found in affluent countries

Question 8

What will happen to the population if the pre-reproductive age group is the largest?

Answer 8

• the population will increase

Question 9

What will happen to the population if the pre-reproductive age group is the smallest?

Answer 9

• the population will decrease

Question 10

What is the growth like in a population with more old, non-productive individuals?

Answer 10

• it will grow more slowly

Question 11

What can population graphs do?

Answer 11

• assess how rapidly or slowly a nation’s population is growing
• show if a country is more or less developed
• show the number of people per age range in the country
• show the history of a nation’s growth
• be useful in determining the number of economic dependents being supported

Question 12

How can epidemics cause the make-up of a population to change?

Answer 12

• HIV/AIDS causing the deaths of many sexually active young men and women particularly in developing countries

Question 13

How can immigrants cause the make-up of a population to change?

Answer 13

• high proportions of young immigrants being rapidly absorbed
• or losses due to emigration of able-bodied young adults

Question 14

How can war cause the make-up of a population to change?

Answer 14

• losses due to able bodied men fighting wars

Question 15

How can economic crisis cause the make-up of a population to change?

Answer 15

• reduced birthrates during times of economic crisis