352 public questions tagged with this topic.
Biodiversity contributes to ecosystem productivity and stability. Habitat loss and fragmentation, overexploitation, alien species invasions, and co-extinctions are the major causes of biodiversity loss described in NCERT.
Ref: NCERT Class 12 Biology Chapter 13: Biodiversity and Conservation Loss of Biodiversity - Causes - Habitat Loss Overexploitation
Pyramids of biomass in aquatic ecosystems can be inverted because phytoplankton have lower biomass than the organisms feeding on them.
Ref: NCERT Class 12 Biology Chapter 12: Ecosystem Ecological Pyramids - Number Biomass Energy
Deserts have the lowest net primary productivity due to limited water availability and extreme climatic conditions.
Ref: NCERT Class 12 Biology Chapter 12: Ecosystem Productivity - Primary Secondary GPP NPP
Despite their vast area, oceans have low productivity due to the limited availability of essential nutrients in deep waters.
Ref: NCERT Class 12 Biology Chapter 12: Ecosystem Productivity - Primary Secondary GPP NPP
Net Primary Productivity (NPP) is the amount of energy left after plants use some for respiration (R), calculated as NPP = GPP - R.
Ref: NCERT Class 12 Biology Chapter 12: Ecosystem Productivity - Primary Secondary GPP NPP
NPP is always less than GPP because it accounts for the energy lost through respiration.
Ref: NCERT Class 12 Biology Chapter 12: Ecosystem Productivity - Primary Secondary GPP NPP
Primary productivity is affected by sunlight, nutrient availability, and temperature, but decomposer activity mainly influences decomposition.
Ref: NCERT Class 12 Biology Chapter 12: Ecosystem Productivity - Primary Secondary GPP NPP
Energy is not recycled; it flows in one direction through the ecosystem and is eventually lost as heat.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Interactions - Mutualism and Amensalism
The logistic growth model considers carrying capacity, population density, and birth/death rates, but not mutation rate.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Growth - Exponential and Logistic Models
Logistic growth includes a carrying capacity, limiting population growth, while exponential growth continues unchecked under ideal conditions.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Growth - Exponential and Logistic Models
Altruistic behavior benefits others at the expense of the individual, such as worker bees sacrificing their ability to reproduce to help the queen.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Growth - Exponential and Logistic Models
Logistic growth occurs when population growth slows as it reaches carrying capacity due to resource limitations.
Ref: NCERT Class 12 Biology Chapter 11: Organisms and Populations Population Growth - Exponential and Logistic Models
