Class 11 NEET Biology Plant Kingdom Questions Part 1

(c) : In Ulothrix/Spirogyra reduction division (meiosis) occurs at the time of zygospore formation. Plant body of Ulothrix and Spirogyra, is gametophytic (haploid), they produce zoogametes (n) which fuses to form zygosporic ( 2n ) diploid, which is a resting spore. Onset of favourable condition zygospore undergoes reductional division, or meiosis to produce zoo-meiospores.