Question

In which of the following classes of fungi, sexual reproduction is absent?
A. Basidiomycetes
B. Deuteromycetes
C. Phycomycetes
D. Ascomycetes

Answer 1

Hint: The fungi ar the organisms which are known to bereproducing with the help of sexual as well as asexual reproduction method, but there are classes where sexual reproduction is not found. Those fungi are known as fungi imperfecti. By comparing the reproduction modes in all the options we can have our answer.

Complete answer:
We all know that the fungi are almost similar to the plants in almost every characteristic. Their habitat is also the same. Plants are known to prepare their own food and the fungi can also prepare their own food and they do not have to rely on anyone to achieve its nutritional requirements.
The sexual reproduction of the fungi is carried forward with the help of spores which almost all of the fungi are producing. On the other hand, the fungi acquire various number of processes to achieve its mode of asexual reproduction. One of the modes of asexual reproduction is budding followed by fragmentation. The process of formation of spores by the fungi is known as sporulation. Basidiomycetes produces spores known as basidiospores and they grow on the structure called basidium. If we recall the chapters from our smaller classes, we know that basidiomycetes are capable of doing both sexual and asexual reproduction. Ascomycetes is also reported to have been able to achieve both sexual and asexual reproduction by the help of spores which it produces and is stored in the sac is called asci. Now if we talk about the other remaining options, we have phycomycetes and deuteromycetes. Phycomycetes are known to be living in the aquatic habitat and the reproduction is by the help of zoospores. Deuteromycetes is known to produce no spores and no one has reported about the production of spores yet so our answer should be the deuteromycetes. Deuteromycetes is also known as the incomplete fungi due to its ability to produce asexually.

So, the correct answer is option B.

Note: The spore formed by the sexual reproduction of phycomycetes is known as zygospore, basidiomycetes is known as basidiospore and ascomycetes is known as the ascospore. The
spores are formed by the fusion of male and female gametes. Among the options provided phycomycetes is the only water living fungi and it should not be confused as it is water living and therefore it will not be able to reproduce sexually.