Class 12th Biology 2017 Set2 Delhi Board Paper Solution
Explain the role(s) of the following in biotechnology.
(b) Gel-electrophoresis
Gel-electrophoresis:
It is the technique which allows the visualisation of separated fragments of DNA on an agarose gel matrix. Since, the DNA fragments are negatively charged molecules, they separate and move towards the anode ( + ve) under the influence of an electric field. DNA fragments are separated on the basis of their size through the sieving effect provided by the gel.
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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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