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
Correct answer: B. zero
- A. 05
- B. zero
- C. 10
- D. 15
Explanation
Natality and immigration positively contribute to the population growth while mortality and emigration are negative factors. In the given question, The net increase in population is natality + immigration = 250 + 20 = 270 The net decrease in population is mortality + emigration = 240 + 30 = 270 Thus, net increase in population = 270 - 270 = 0
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Ecosystems include biotic and abiotic components, food chains and webs, energy flow, nutrient cycles, populations and ecological relationships. Pollution and conservation cover air, water, soil and noise pollution, their effects on organisms, biodiversity loss, protected areas, sustainable resource use and methods for reducing environmental damage.
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