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प्रश्न
Give two examples of vestigial organs in human beings and plants.
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उत्तर
Vestigial organs are remains of a structure that were functional in some ancestor but is no longer functional in present body.
Some examples of such organs in humans are:
(a) Appendix: The appendix is a small projection of the side of the large intestine near the cecum. It looks kind of like a tail and is found near where the small and large intestines meet. No one knows the actual original function of the appendix.
(b) The tail bone: Attached to the bottom of the sacrum is the coccyx or tailbone. This small, bony projection seems to be a leftover structure of primate evolution. It is believed that human ancestors once had tails and lived in trees. The coccyx would be where the tail was attached to the skeleton.
Some examples of such organs in plants are:
(1) Sexual organs of dandelions: The common dandelion reproduces asexually through a process known as apomixis. However, they still have all of the functional parts that most flowering plants use to reproduce sexually, namely the stamen and pistil.
(2) Grass often has small, undeveloped structures that strongly resemble those of flowering plants.
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संबंधित प्रश्न
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(A) Sweet potato and potato
(B) Sweet potato and tomato
(C) Carrot and potato
(D) Radish and carrot
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(A) Potato and sweet potato
(B) Carrot and radish
(C) Carrot and tomato
(D) Tomato and radish
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P. Forelimb of a frog and forelimb of a lizard
Q. Forelimb of a bird and forelimb of a human
R. Wings of a parrot and wings of a butterfly
S. Wings of a bird and wings of a bat
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(A) P and Q
(B) Q and R
(C) R and S
(D) P and S
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(a) homologous organs
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(c) analogous organs
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(a) analogous organs
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(c) digestive organs
(d) homologous organs
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| (a) | (b) | (c) |
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