CBSE 2022 · Region 3 · Set 2 · Q1 · 2 marks
Observe the schematic representation given above and answer the following questions :(i)Identify A and B.(ii)Calculate the growth rate of bacteria in a curd sample, where $\displaystyle 1$ million bacteria increased to two million, within a period of one hour.Identify the type of pyramid given above. Write the identifying feature on the basis of which you identified it.
Observe the schematic representation given above and answer the following questions :
(i)
Identify A and B.
(ii)
Calculate the growth rate of bacteria in a curd sample, where $\displaystyle 1$ million bacteria increased to two million, within a period of one hour.
Identify the type of pyramid given above. Write the identifying feature on the basis of which you identified it.
Marking-scheme solution
(a) (i) \(\displaystyle A\) - Mortality/No. of deaths in population B - Natality/No. of births in population
(ii) $\displaystyle 1$ bacteria per bacteria per hour [Growth rate \(\displaystyle =\underline{2}\) million -$\displaystyle 1$ million] $\displaystyle 1$ million
Expanding, Age pyramid
The number of individuals in the 'pre-reproductive' age group is more than the 'reproductive' age group.
EcosystemEnergy FlowApplyvery_short_answermedium
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CBSE Class 12 Biology past-paper question from the 2022board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.