What term describes the total number of people living in a country or the world?
Population size
What is the demographic transition model used for?
To show changes in birth and death rates over time as countries develop
What is carrying capacity?
The maximum population size an environment can sustainably support
Name one way human population growth affects the environment.
Deforestation, pollution, habitat loss, climate change, overfishing
How can scientists estimate future population size?
Using models based on birth rates, death rates, and migration trends
What has been the general trend in global human population over the past 200 years?
Rapid increase, especially since the Industrial Revolution
How many stages are in the classic demographic transition model?
Four (sometimes five in modern models)
Name one factor that affects carrying capacity.
Food availability, water, habitat, or disease
How does increased urbanization impact ecosystems?
Reduces habitat, increases pollution, and fragments landscapes
What is one limitation of population predictions?
Unexpected events like pandemics, wars, or technological advances
How do population pyramids help visualize age and gender distribution in a country?
They show the number of people in each age group for males and females
Give an example of a country in Stage 2 of the demographic transition.
Nigeria or Afghanistan (high birth rate, declining death rate)
How does technology influence human carrying capacity?
It can increase capacity by improving food production and resource management
Why does rapid population growth threaten biodiversity?
More land and resources are used → habitats destroyed → species decline
How could an aging population affect a country’s economy and environment?
Fewer workers → higher healthcare costs → possible changes in resource use
Explain why some countries have rapidly growing populations while others grow slowly.
Differences in birth rates, death rates, and economic development
How does Stage 4 differ from Stage 2?
Stage 4 has low birth and death rates → stable population
Why might carrying capacity vary over time?
Environmental changes, resource depletion, or technological advances
How does overpopulation contribute to climate change?
Higher energy use, deforestation, and greenhouse gas emissions
Why is population density important for planning cities and infrastructure?
High density increases demand for housing, transportation, and services
What is one historical factor that caused a dramatic population increase?
Industrialization and advances in medicine
How might policies like family planning influence a country’s demographic stage?
They can reduce birth rates, slowing population growth
What could happen if a population exceeds its carrying capacity?
Resource shortages, environmental degradation, population decline
What is one potential solution to reduce environmental impact from population growth?
Sustainable resource use, renewable energy, family planning, or education
What are two major global challenges if the population continues to grow rapidly?
Food security and environmental sustainability