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Assertion (A ) : The long neck of giraff...

Assertion (A ) `:` The long neck of giraffe is due to centripetal selection.
Reason (R ) `:` During directional selection when the mean value of phenotype coincide with new optimum environmental conditions. Centripetal selection takes over.

A

Both (A ) and (R ) are true and (R ) is the correct explanation of (A).

B

Both (A ) and (R ) are true but (R ) is not the correct explanation of (A)

C

(A ) is true statement but (R ) is false

D

Both (A ) and (R ) are false

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The correct Answer is:
A
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GRB PUBLICATION-ORGANIC EVOLUTION -REPRODUCTIVE ISOLATION
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  2. Statement (S): Species are groups of potentially interbreeding natural...

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  3. Assertion (A ) : The long neck of giraffe is due to centripetal select...

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  4. Arrange the periods of palaeozoic era in ascending order in a geologic...

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  5. The natural selection that acts against change in form and keeps the p...

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  6. The formation of two species from one ancestral species is known as

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  7. Which of the following have not left any evidence of organic evolution...

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  8. The presence of recessive trait in a large population is be 16% the fr...

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  9. Frequencyof an autosomal recessive lethal gene is 0.4 Frequency of car...

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  10. Where there is sustained directional change in the average characters ...

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  11. Plants fo the Galapagos Islands resembles most closedly to the plants ...

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  12. Inclusive fitness theory is proposed by

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  13. Prototherians are connecting link between :

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  14. Darwin finches are related to which of the following evidences ?

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  15. Allopatric speciation is due to

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  16. Which one is linked to evolution ?

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  17. Which of the following is not a concept of Lamarck ?

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  18. Competition of species leads to :

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  19. The idea of ''survival of the fittest'' was given by

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  20. Vestigial organs present in an adult individual are example of basis o...

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