Biology · Reproductive Health · NEET
NCERT stresses the FALL in death rate, MMR and IMR as the main reasons, not a rise in birth rate. Better health facilities and better living conditions meant more people survived and lived longer. Birth rate stayed high while death rate dropped fast, so the gap between births and deaths widened and population grew rapidly. For NEET, remember: it is the falling death rate, not a new spike in births, that drives the explosion.
MMR is Maternal Mortality Rate (deaths of mothers during pregnancy or childbirth). IMR is Infant Mortality Rate (deaths of babies under 1 year). A fall in both means more mothers and more babies survive. NCERT lists 'a decline in MMR and IMR' as a direct reason for the increasing population, because fewer deaths in these two groups add more surviving people every year.
Because a large number of people were already in the reproductive age group (roughly the group able to have children). Even with awareness, this big base of young couples keeps producing many babies. NCERT names 'increase in number of people in reproductive age' as a key reason. This is why a growing population shows a broad-based age pyramid with more pre-reproductive and reproductive individuals.
No. It mainly means fewer people are dying, not that each couple has far more children. Improved health lowered death, MMR and IMR, so more people survive to adulthood and can reproduce. The number of people in reproductive age rose, so total births per year rose even if family size did not jump dramatically.
NCERT states the world population was around 2 billion (2000 million) in 1900, rose to about 6 billion by 2000, and reached 7.2 billion in 2011. India showed a similar trend. These numbers are often quoted in NEET, so remember 2 billion (1900) to 6 billion (2000) as the 'rocketed' figures.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
It is a very rapid rise in the number of people in a short time, seen when world population went from about 2 billion in 1900 to about 6 billion by 2000.
A rapid fall in death rate, in maternal mortality rate (MMR) and infant mortality rate (IMR), together with an increase in the number of people in the reproductive age group. Better health facilities and living conditions caused these falls.
Better health increased population. It did not add births directly, but it lowered deaths, MMR and IMR, so more people survived and lived longer, causing an explosive rise in numbers.
About 2 billion in 1900, about 6 billion by 2000, and 7.2 billion in 2011. India followed a similar rising trend.
It sets up the next idea, population stabilisation and birth control, and NCERT directly asks 'What are the suggested reasons for population explosion?', so options on death rate, MMR, IMR and reproductive age are commonly tested.
