Question

.......................are thick-walled spores produced by Rhizopus which are capable of withstanding unfavourable conditions?
A. Chlamydospores
B. Zoospores
C. Oidia
D. Sporangiospores

Answer 1

Hint:
There are different types of spores which germinate to produce a new individual. Look for the spores produced by the fungi Rhizopus and have a thick wall. Having a thick wall ensures stability in unfavourable conditions.

Complete answer:
Spores are minute, single-celled thin walled propagules which germinate to produce new individuals. There are several kinds of spores which occur in monerans, protistans, fungi and algae.
Chlamydospores are thick-walled spores produced from Rhizopus hyphal cells. They store reserved food materials and are capable of withstanding unfavourable conditions.
The zoospores are special kinds of motile and flagellated spores produced inside the zoosporangia. They are generally naked (without a cell wall). With the help of flagella, spores are able to swim in aquatic habitats for proper dispersal. The reproduction by zoospores occurs in some lower fungi Phycomycetes (e.g., Achlya, Saprolegnia, Albugo, Phytophthora, etc.) and simple plants such as algae.
In Oidia, the hypha breaks up into its component cells or small pieces which act like spores. These are thin-walled and do not store reserved food material. The formation of oidia is generally observed under the conditions of excess water, sugar and certain salts. Oidia germinate immediately after liberation and cannot survive under unfavourable conditions.
Sporangiospores are non-motile spores produced inside the sporangia. Sometimes these spores are also called endospores. They are seen in Rhizopus. These spores are thin-walled. Dispersion is generally seen by wind and they germinate to produce new mycelium.
Hence, the correct answer is chlamydospores

Option ‘A’ is correct

Note:
There is another type of spore: Conidia. They are formed in Penicillium. These are non-motile spores. They are produced singly or in chains by a constriction at the tip or lateral side of special hyphal branches, called conidiophores. They are produced exogenously. Dispersed is done by wind and they germinate directly by giving out germ tubes.