Question

After karyogamy followed by meiosis, spores are produced exogenously in

• A. Soccharomyces
• B. Neurospora
• C. Agaricus
• D. Alternaria

Answer 1

The Correct Option is C

The question asks about the production of spores after karyogamy and meiosis, specifically exogenously. The correct answer to this question is Agaricus. Let's analyze why this option is correct and explore why the others are not suitable.

Karyogamy is the fusion of nuclei, followed by meiosis which is a type of cell division that reduces the chromosome number by half. In certain fungi, spores are produced exogenously, meaning they develop outside the parent organism.

1. Agaricus: This belongs to the class Basidiomycetes. In this class, the basidiospores are produced outside, on a structure known as the basidium. Therefore, Agaricus is correct since it produces spores exogenously after karyogamy and meiosis.
2. Soccharomyces: This is a genus of fungi that reproduces by budding and is a part of the class Ascomycetes. Its spores, called ascospores, are produced endogenously within an ascus. Hence, it does not fit the requirement of exogenously produced spores.
3. Neurospora: Another member of Ascomycetes, it produces endogenously formed spores inside an ascus, not exogenously.
4. Alternaria: A genus of Deuteromycetes which reproduces asexually by conidia, but this does not follow the process of karyogamy followed by meiosis for spore production.

In conclusion, basidiospores formed in Agaricus are exogenously produced on basidium, aligning with the condition described in the question. This confirms Agaricus as the correct option.