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Biology · 2022 · 2 marks
CBSE 2022 · Region 3 · Set 2 · Q1
(a) Observe the schematic representation given above and answer the following questions: (i) Identify A and B. (ii) Calculate the growth rate of…
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
OR
(b)
Expanding, Age pyramid
The number of individuals in the 'pre-reproductive' age group is more than the 'reproductive' age group.
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CBSE Class 12 Biology past-paper question from the 2022 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.