General Mycology
PLP 427/527

Zygomycota and Glomeromycota - Study Questions

1. Explain why the Zygomycota are considered to be evolutionarily intermediate between the lower fungi we have previously considered, and the Ascomycota, Basidiomycota, and Deuteromycota.

a. What characteristics are shared by members of the Zygomycota? What characteristics do they share with the Glomeromycota?

b. What characteristics are unique to the Glomeromycota?

2. Sometimes mycologists use the same terms for two different things. For example, the zoospore pattern of Saprolegnia is said to be dimorphic, as is the life style of Mucor rouxii. What does dimorphic mean in general, and how does it apply to M. rouxii.?

3. Blakeslee called the different mating types of Rhizopus +/- instead of male/female. Why did he do that?

4. Rhizopus stolonifer and Pilobolus crystallinus are both extremely successful at dispersing their asexual spores, yet you will find R. stolonifer everywhere, but not P. crystallinus. Explain how their dispersal methods differ and why their ranges differ.

5. What are two ways that the Entomophthorales differ from other members of the Zygomycota?

6. How do + and - sporangiospores of Rhizopus differ?

7. Why is the sexual reproductive method of the Zygomycota called gametangial fusion, or gametangial copulation?

8. What are three different modes of dispersal used by species of the Zygomycota? (BIg hint: think of Rhizopus, Pilobolus and Spirodactylon)

9. Are the Zygomycota a monophyletic group? Explain.

10. What criteria led to the separation of the Glomeromycota into a separate phylum, in 2001? Is this separation thought to be due to their recent evolution as a separate group?

11. What is the environmental role of the Glomeromycota? Approximately how many Glomeromycota species are there, and how many species are they associated with?

12. Indicate the ploidy of the following:
a. mycelium of Rhizopus
b. sporangiospore of Pilobolus
c. zygospore of Rhizopus
d. rhizoids of Rhizopus

13. Define:

antheridiol-
rhizoids-
stolon-
zygospore-
columella-
dimorphic-
vesicular arbuscular
appendages
merosporangium
sporangiolum