Class 12th Biology 2013 Set2 Delhi Board Paper Solution
(a) Draw a labelled schematic diagram of the transverse section of a mature anther of an angiosperm plant.
(b) Describe the characteristic features of an insect pollinated flower.
OR
(a) Describe the events of spermatogenesis with the help of a schematic representation.
(b) Write two differences between spermatogenesis and oogenesis.
(a)
| Spermatogenesis | Oogenesis |
| (i) It occurs in testes | It occurs in ovaries |
| (ii) A spermato gonium forms 4 spermatozoa | An oogonium forms one ovum |
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(c) Behavioural adaptations in animals
(d) Importance of light to plants
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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)
(f) The process of release of the ovum from a mature follicle is called__________.
(g) Ovulation is induced by a hormone called the __________.
(h) The fusion of male and female gametes is called _____________.
(i) Fertilisation takes place in _____________.
(j) Zygote divides to form _____________which is implanted in uterus.
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