60 public questions tagged with this topic.
Thomas Malthus’s work on population growth and resource limitation influenced Darwin’s concept of natural selection. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function.
An inverted age pyramid indicates a declining population, with a higher number of post-reproductive individuals and fewer young individuals. This follows from latest NCERT 2026-27 principle explaining the concept clearly for NEET students in simple steps as per rationalized syllabus.
Ref: NCERT Biology Textbook - Latest Edition for Academic Session 2026-27 (Botany section, Rationalized Textbook for Class XI and XII), Chapter: Biology - Botany portion (Latest NCERT Textbooks for Academic Session 2026-27 -
Competition negatively affects both species as they compete for the same limited resources.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Interactions - Parasitism and Commensalism
Keystone species are not necessarily the most abundant, but they play a crucial role in maintaining ecosystem structure.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Interactions - Predation and Herbivory
Succession generally leads to a stable climax community, not an unstable one.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Interactions - Predation and Herbivory
K-selected species produce fewer offspring, invest in parental care, and have longer lifespans.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Life History Variations and Population Interactions - Overview
Age structure refers to the relative proportion of individuals in different age groups within a population.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Life History Variations and Population Interactions - Overview
K-selected species invest in fewer offspring with high parental care, ensuring their survival.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Life History Variations and Population Interactions - Overview
The intrinsic rate of natural increase (r) measures how fast a population can grow under ideal conditions.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Life History Variations and Population Interactions - Overview
As population size nears carrying capacity (K), competition increases and growth slows due to limited resources.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Growth - Exponential and Logistic Models
When a population exceeds carrying capacity, resource limitations lead to increased mortality and decreased reproduction.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Growth - Exponential and Logistic Models
Immigration refers to the movement of individuals into a population, increasing its size.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Attributes - Birth Death Sex Ratio Age Distribution
