If the filament of spirogyra is broken in to fragments. What do you observe?
Answers
Answer:
If the filament of spirogyra is broken into fragments then the broken filament will develop into a new plant .
Explanation:
Spirogyra are free-floating green algae present in freshwater habitats such as ponds, lakes, etc. Spirogyra are commonly known as “water silk or pond silk”. They have a filamentous and unbranched vegetative structure. There are around 400 species of Spirogyra found. The genus Spirogyra is named after the unique spiral chloroplast present in the cells of algae.
Spirogyra are photosynthetic and contribute substantially to the total carbon dioxide fixation carried out. They increase the level of oxygen in their habitat. Many aquatic organisms feed on them.
Spirogyra undergo vegetative, asexual and sexual reproduction. The life cycle of Spirogyra is haplontic, i.e. the dominant stage is free-living haploid (n) gametophyte and the sporophyte is represented only by the diploid zygote (2n)
Vegetative reproduction is by fragmentation. Under the favourable conditions, vegetative reproduction is the preferred mode of reproduction.
The vegetative filament after fragmentation develops into a new filament. Each fragment undergoes multiple division and elongation to form a new filament
Fragmentation can be due to mechanical injury or dissolution of the middle lamella with a change in the salinity and temperature of the water
Sometimes the middle lamella of one cell protrudes into an adjacent cell resulting in the breakage of the filament
Asexual reproduction is found in few of the species of Spirogyra. Asexual reproduction is by the formation of azygospores, akinetes or aplanospores.
Formation of aplanospores occurs under unfavourable conditions. The protoplast shrinks and forms a wall around it. This results in the formation of aplanospores
Akinetes are also formed similarly, but they have a thicker cell wall of cellulose and pectin
Akinetes and aplanospores are non-motile spores, which develop into a new filament under favourable conditions after the decay of the parent filament
Azygospores are also known as parthenospores. These are the gametes, that failed to fuse during sexual reproduction and develop into a new filament asexually
Sexual reproduction in Spirogyra is isogamous, i.e. male and female gametes of similar size fuse together in the sexual reproduction.
Sexual reproduction is by conjugation. Conjugation is of two types, Scalariform conjugation and lateral conjugation.