After the 1850s in the post-industrialization era in England, the expected effect of natural selection on the number of white-winged moths as compared to the dark-winged moths was:
Show Hint
- Less in number
- More in number
- Both were less in number
- Both were more in number
The Correct Option is A
Solution and Explanation
- White-winged moths were more visible to predators, reducing their population.
Top Questions on Pollination
Many of the flowering plants producing hermaphrodite flowers have developed many devices to discourage self-pollination and to encourage cross-pollination. Given below is a picture of one such outbreeding device in a flowering plant. Study the picture and answer the questions that follow:
(a) Explain how the given type of pollination is advantageous to the plant.(b) Can this flowering plant show geitonogamy? Justify your answer.
- CBSE CLASS XII - 2025
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Questions Asked in CBSE CLASS XII exam
A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:(iii) (b) If the foot of the ladder, whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance \( y \) is \( 2 \, \text{m/s} \), then at what rate is the height on the wall \( x \) increasing when the foot of the ladder is 3 m away from the wall?
- CBSE CLASS XII - 2025
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- Vishesh, Manik and Amit were partners in the ratio 5 : 4 : 1. Amit retired on 31st March, 2024. Vishesh and Manik decided to share Amit’s share in the ratio 2 : 3. What will be the new profit sharing ratio between Vishesh and Manik?
- CBSE CLASS XII - 2025
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- CBSE CLASS XII - 2025
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