Question

Auxospore forrmation is seen in

• A. Nostoc
• B. Yeast
• C. Diatoms
• D. Agaricus

Answer 1

The Correct Option is C

Diatoms have cell walls containing silica, constructed in two overlapping halves epitheca and hypotheca which fit together like two parts of a soap box (pennate types) or pair of Petridishes (centric types) . The common mode of multiplication is by binary fission. During fission, the epitheca and hypotheca slightly separate apart with two daughter protoplasts in between, and new cell wall halves are formed. In case, where parent hypotheca serves as the epitheca for the daughter cell, the resulting daughter cells. become smaller than the parent cell (because in? parent cell hypotheca is smaller than epitheca to fit into it). On the other hand, in case where parent epitheca serves ?as the epitheca, the resulting daughter cell is of the same size as the parent cell. However, fertilization .during sexual reproduction produces a zygote which grows in size and forms a rejuvenescent cell, called auxospore. In, this manner, the diatoms size is restored.

Answer 2

Auxospore is a form of reproduction that is observed in diatoms. Diatoms are a unicellular algae and are known for their silica cell walls. These are called frustules. 

The asexual reproduction in diatoms is seen through cell division. But in this case, the size of the daughter's cells decreases with every division. To maintain the original size auxospore formation takes place. 

Auxospore formation leads to a larger frustule and the older one gets rupture. The larger frustules known as auxospore then ruptures and restores the size of the diatoms