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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 populations is :

A

10

B

156

C

`05`

D

Zero

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The correct Answer is:
D
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MODERN PUBLICATION-ORGANISMS AND POPULATIONS -COMPETITION FILE (OBJECTIVE TYPE QUESTIONS)(A. MULTIPLE CHOICE QUESTIONS)
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  2. Cuscuta is an example of

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

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  4. A sedentary sea anemone gets attached to the shell lining of hermit cr...

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  5. Full name of professor Misra who is known as the Father of Ecology in ...

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  6. Population growth curve is sigmoid, if the growth pattern is

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  7. Temperature increases with height in which of the spheres

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  8. (dN)/(dt) rN equation is applicable to …………..population growth.

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  9. A few normal seedlings of tomato were kept in a dark room. After few d...

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  10. The zone of atmosphere in which the ozone layer is present is called

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  11. Mycorrhiza promotes plant growth by

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  12. Most animals are tree dwellers in a

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  13. The following graph depicts changes in two populations (A and B) of he...

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  14. In which of the following interaction both partners are adversely affe...

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  15. The figure given below is a diagrammatic representation of response of...

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  16. Allen's rule applies to:

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  17. Troublesome American water weed found in Inida is

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  18. The characters such as pointed elongated snout, strong and stout forel...

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  19. A cuckoo laying eggs in the nest of other species of birds is an examp...

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  20. One of the following pair of animals is an example of commensalism :

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