Class 12th Biology 2017 Set3 Delhi Board Paper Solution
Give an example of an angiosperm seed that has a perisperm. Name the part the persiperm develops from.
The persiperm develops from residual,persistent nucellus in some seeds. It is found in black pepper and beat.
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(b) Adaptations of plants to water scarcity
(c) Behavioural adaptations in animals
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Fill in the blanks:
(a) Humans reproduce __________. (asexually/sexually)
(b) Humans are__________. (oviparous/viviparous/ovoviviparous)
(c) Fertilization is __________ in humans. (external/internal)
(d) Male and female gametes are __________. (diploid/haploid)
(e) Zygote is __________. (diploid/haploid)
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(i) Fertilisation takes place in _____________.
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