which organism undergoes the sexual process of conjugation
Spirogyra forms nonmotile gametes. Spirogyra undergoes sexual reproduction using a process called conjugation. First two haploid filaments of opposite mating types (+ and -) line up side by side. Each cell then forms an extension that grows towards a cell on the opposite strand. The tubes fuse forming conjugation tubes. The content from the cell of (-) strain travels through the tube and fuse with the cytoplasm of the cell of the (+) strain. The protoplast (the entire living portion of the cell) of each individual organism thus act as an isogamete until they fuse. The diploid zygote develops the zygospore.