Question

Fertilisation is internal is spirogyra. Where would you get zygospores, if 3 filaments are conjugating by scalariform conjugation?

• A. Lateral filaments
• B. Central filaments
• C. Central filament and both lateral filaments
• D. Either central or lateral filament

Answer 1

The correct option is D Either central or lateral filament

• In Spirogyra, both lateral and scalariform conjugation has been observed.
• During the scalariform conjugation, a pair of filaments either central or lateral align themselves laterally and connects through branch-like conjugation tubes.
• This tube grows from each of the filament and meets in the centre to form a space in which zygote moves. Each zygote will grow in a filament.
• During the lateral conjugation, gametes produced by adjacent cells on the same filament meet and develop within a short, curved conjugation tube.

So, the correct option is D.