Reproduction in Spirogyra

Spirogyra is a filamentous algae. It reproduces asexually by conjugation.

1. Asexual Reproduction in Spirogyra

Fragmentation under ideal condition of food, sunlight and water a mature filament of spirogyra simply breaks into pieces. Each fragment forms a new filament.

Spirogyra fragmentation:

2. Sexual Reproduction in Spirogyra

There are two types of sexual reproduction in spirogyra. These are: lateral conjugation and scalariform conjugation.

(a) Scalariform Conjugation

In this, two filaments lie side by side, particularly or fully along their lengths. One cell from each filament produces tubular protuberances called conjugation tubes. These elongated and fuse to form conjugation canal. The mobile cytoplasm (male cytoplasm) moves through the canal and fuses with the cytoplasm of the other filament. The gametes in both fuses to form a zygospore. The zygospore germinates and forms a new filament.

Scalariform conjugation in spirogyra:

(b) Lateral Conjugation

Conjugation occurs between two adjacent cells on the same filament. Two common adjoining cells near their common transverse wall produce protuberances called conjugation tubes, which further form conjugation canal upon contact. The male cytoplasm migrates through the conjugation canal, fuses with the female. This union produces a zygospore. Each zygospores germinates and forms a new filament.

EVALUATION (POST THE QUESTION TITLE AND YOUR ANSWER IN THE QUESTION BOX BELOW FOR EVALUATION AND DISCUSSION)

Describe a sexual reproduction in spirogyra.