CBSE 2026 · Region 2 · Set 1 · Q20 · 2 marks
In some cases, measuring population density by counting individuals may not be feasible. Mention two other parameters that can be used and justify their use with suitable examples.What factors contribute to the Amazonian rain forests in South America being the most biodiverse regions on Earth ?
In some cases, measuring population density by counting individuals may not be feasible. Mention two other parameters that can be used and justify their use with suitable examples.
What factors contribute to the Amazonian rain forests in South America being the most biodiverse regions on Earth ?
Marking-scheme solution
$\displaystyle \star$ Percent cover / biomass, In an area if there are $\displaystyle 200$ carrot grass or Parthenium plants but only single huge banyan tree with a large canopy stating that population density of banyan is low amounts to underestimating the enormous role of Banyan.
$\displaystyle \star$ Relative density, laboratory culture in a petri dish / fish caught per trap
$\displaystyle \star$ Indirect estimate, tiger census in national parks and tiger reserves is often based on pug marks and fecal pellets.
(Any Two)
$\displaystyle \star$ Amazonian Rain Forests in South America has remained relatively undisturbed for millions of years.
$\displaystyle \star$ It is less seasonal more constant and predictable.
$\displaystyle \star$ More solar energy available in tropical areas that contributes to higher productivity and more diversity
(Any Two)
Organisms and PopulationsPopulationsUnderstandvery_short_answermedium
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CBSE Class 12 Biology past-paper question from the 2026board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.