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A biologist studied the population of ra...

A biologist studied the population of rats in a barn . He found that the average natality was 250 , average mortality 240 , immigration 20 and emigration 30. The net increase in population is :

A

Zero

B

10

C

15

D

5

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USHA PUBLICATION-ORGANISMS AND ENVIRONMENT-EXERCISE
  1. Age pyramid with broad base indicates :

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  2. Grazing benefits the grasses . The term for this interaction should be...

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  3. A biologist studied the population of rats in a barn . He found that t...

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  4. Which is not a parasitic adaptation :

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  5. Sigmoid // logistic growth curve is represented by :

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  6. Latitude range with maximum species diversity is :

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  7. What is represented by the sketch ? A , B , C , D is community of four...

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  8. Number of age groups in a population is :

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  9. Many tribes living in high altitudes of Himalayas have :

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  10. The two basic processes which contribute to a decrease in population d...

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  11. Which of the following interactions is / are examples of competition :...

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  12. Which Of the following is correct

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  13. The removal of keystone species will affect :

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  14. Which forest plants control light conditions at the ground ?

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  15. Sal ( Shorea robusta ) forest is a :

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  16. The plant which produces highly poisonous cardiac glycosides is :

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  17. Which helps in maintaining species diversity in a community ?

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  18. The interaction between the organisms of one of the following pairs is...

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  19. The first plants to appear in a badly burnt forest area will most prob...

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  20. Which statements correlate with diagram ?

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