Q12 of 43 Page 1

State ‘two’ observations made by German naturalist, Alexender von Humboldt during his extensive explorations in South American jungles.

OR


If in a population of size ‘N’ the birth rate is represented as ‘b’ and the death rate as ‘d’, the increase or decrease in ‘N’ during a unit time period ‘t’ will be:



The equation given above can also be represented as:



What does ‘r’ represent? Write any one significance of calculating ‘r’ for any population.


Alexender von Humboldt during his extensive explorations in South American jungles made the following observations:

• Within a region species richness increases with increasing explored area but only upto a limit.


• This relation for a wide variety of taxa turns out to be a rectangular hyperbola.


OR


‘r’ represents the intrinsic rate of natural increase. It is an important parameter for assessing impacts of any biotic or abiotic factor on population growth.


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When and where do tapetum and synergids develop in flowering plants? Mention their functions.

OR


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(a) Germ pore


(b) Sporopollenin


(c) Generative cell


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