Question

More common type of conjugation in Spirogyra is

• A. Terminal
• B. Indirect lateral
• C. Direct lateral
• D. Scalariform

Answer 1

Answer: (D)

Scalariform

In Spirogyra, sexual reproduction occurs by conjugation, which is of two types:

1. Scalariform conjugation: It is the most common type of conjugation in Spirogyra. The two filaments function and male and female. Their cytoplasmic content is rounded up, leading to the formation of gametes. Via the conjugation tube, the male gamete is transferred to the female filament and fuses with the female gamete to form the zygote. The zygote becomes zygospore by developing a thick wall. The male filament empty and the female filament carries the zygospore.

2. Lateral conjugation: This type of conjugation occurs within the same filament. In direct lateral conjugation, the content from one cell acting as male gamete moves into the adjacent cell acting as female gamete through a pore and the zygospore is formed. In indirect lateral conjugation, the conjugation tube is formed between the adjacent cells and the male gamete content is transferred to the female gamete which is adjacent to the male gamete.

Hence, the correct answer is 'Scalariform'