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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

`05`

B

zero

C

`10`

D

`15`

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The correct Answer is:
B
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TRUEMAN BIOLOGY-ORGANISMS AND POPULASTIONS -Multiple Choice Questions
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  2. Adapative measure to protect against extreme heat by poikilotherms is

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

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

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  5. Just as a person moving from Delhi to Shimla to escape the heat for th...

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  6. A location with luxuriant growth of lichens on the trees indicates tha...

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  7. An association of individuals of different species living in the same ...

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  8. Most animals that live in deep oceanic waters are:

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

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  10. Gause's principle of competitive exclusion states that:

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  11. When does the growth rate of a population following the logistic model...

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  12. Which of the following is correct for r-selected species ?

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  13. If '+' sign is assigned to benefited interaction '-' sign to detriment...

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  14. The principle of competitive exclusion was stated by

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  15. Asymptote in a logistic growth curve is obtained, when

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  16. Plants, which produce characteristic pneumatophores and show vivpary...

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  17. Which one fo the following population interactions is widely used in m...

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  18. In a growing population of a country ,

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  19. Which one of the following plants shows a very close relationship with...

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  20. Natality refers to

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