Photoperiod

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Practice Set I for Biology MCQ

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PARASEXUAL CYCLE (Note FOR UG/PG STUDENTS)

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Parasexual cycle                                  Earlier , it was believed that genetic recombination can only be achieved by sexual reproduction but studies on bacteria have shown that it is also possible through alternative mechanism .Such an alternative mechanism was observed for the first time by Pontecorvo & Raper (1952) seen in Aapergillus nidulans . They observed that in this specialized reproductive mechanism, plasmogamy , karyogamy and meiosis do take place but not at specified time or specified points in the life cycle of the fungus .They considered the group as Deuteromycetes or fungi imperfecti and the specialized cycle of reproduction as “Parasexual Cycle “ Mechanism of parasexual cycle: According to pontecorvo (1958) parasexual cycle in Aspergillus nidulans involves the following step ----- (a) Formati...
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