Population Density and Fluctuation — NEET Biology
📚 Practice ConceptThe size of a population for any species is not a static parameter. It keeps changing with time, depending on various factors including food availability, predation pressure and adverse weather. In fact, it is these changes in population density that give us some idea of what is happening to the population – whether it is flourishing or declining. Whatever might be the ultimate reasons, the density of a population in a given habitat during a given period, fluctuates due to changes in four basic processes,
Which of the above statements are NOT correct? S1: The size of a population for any species is a static parameter, remaining largely constant over time. S2: Natality refers to the number of deaths in a population during a given period. S3: Immigration contributes to an increase in population density, whereas emigration leads to a decrease. S4: Under normal conditions, births and deaths are generally the most important factors influencing population density. S5: When a new habitat is being colonised, immigration may contribute more significantly to population growth than birth rates.
View solution & NCERT explanation
Correct answer: A — S1 and S2 only
This question tests the understanding of basic population attributes and the factors influencing population density and growth as described in NCERT. S1: Incorrect. NCERT states, 'The size of a population for any species is not a static parameter. It keeps changing with time'. S2: Incorrect. NCERT defines 'Natality refers to the number of births during a given period in the population that are added to the initial density.' Mortality refers to the number of deaths. S3: Correct. NCERT explains that 'Immigration is the number of individuals... that have come into the habitat from elsewhere' (increase) and 'Emigration is the number of individuals... who left the habitat and gone elsewhere' (decrease). S4: Correct. NCERT states, 'Under normal conditions, births and deaths are the most important factors influencing population density'. S5: Correct. NCERT mentions, 'if a new habitat is just being colonised, immigration may contribute more significantly to population growth than birth rates.' Therefore, statements S1 and S2 are NOT correct. Option 'A' correctly identifies S1 and S2 as the incorrect statements. Other options contain a mix of correct and incorrect statements or misidentify the incorrect ones. This concept focuses on the dynamic nature of population size and the processes that drive its fluctuations.
What does NCERT say about size population for any?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 176 of the 180 ReNEET 2026 (June 21) questions were already in the MedicNEET question bank before the exam.
176/180MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.