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Problem : Describe the process by which the fruiting bodies of Basidiomycota maintain their binucleate dikaryotic condition.

This process is called formation of clamp connections. First, a bulging pocket forms in the hyphal cell wall at a point between the two nuclei, a and b. Both nuclei then divide mitotically. These divisions are oriented such that the a' nucleus is positioned in the clamp pocket and both the a" and b' nuclei are toward the tip of the hypha, while the b" nucleus takes a posterior position. Next, a cell wall forms between the clamp, the posterior cell and the tip of the hypha, leaving the tip a complete cell with two nuclei. Finally, the clamp curves back toward the hypha and merges with the posterior cell to create another binucleate cell.

Problem : In what structures do plasmogamy, karyogamy and spore formation take place in Basidiomycota?

Plasmogamy takes place between hyphal cells of the mycelium. Karyogamy and spore formation both take place in the basidium.

Problem : How do Basidiomycota reproduce asexually?

Basidiomycota can reproduce asexually by budding of hyphal cells or by production of spores in conidiaphores.

Problem : Describe the haploid and diploid phases of Basidiomycota.

The mycelia of Basidiomycota are haploid. The fruiting body that results from plasmogamy between two mycelia produces binucleate hyphae, but each nucleus is still haploid. In the basidium, nuclei fuse to for a diploid cell, which enters quickly meiosis to become haploid again.
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