Class 12th Biology 2016 Set3 Outside Delhi Board Paper Solution
Name a free-living and a symbiotic bacterium that serve as bio-fertilizer.Why are they so called ?
A free-living bacterium is Azotobacter and and a symbiotic bacterium is Rhizobium. They are called bio-fertilisers because these organisms increase the nutrient quantitiy of soil.
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(b) Adaptations of plants to water scarcity
(c) Behavioural adaptations in animals
(d) Importance of light to plants
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Recently Viewed Questions of Class 12th biology
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Secondary producers are
(a) Herbivores
(b) Producers
(c) Carnivores
(d) None of the above - Q:- From what you have learnt, can you tell whether enzymes are bigger or DNA is bigger in molecular size? How did you know?
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- Q:-
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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