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Flagellated male gametes are present in all the three of which one of the following sets?
A
Zygnema, Saprolegnia and Hydrilla
B
Fucus, Marsilea and Calotropis
C
Riccia, Dryopteris and Cycas
D
Anthoceros, Funaria and Spirogyra
Detailed Solution
The male gametes of bryophytes are biflagellate antherozoids; Riccia is a liverwort.
The male gametes of pteridophytes are multiflagellate (except Selaginella, which has biflagellate gametes); Dryopteris is a fern.
The male gametes of gymnosperms are generally non-motile, except those of Cycas (and Ginkgo), which are large and multiciliate.
So Riccia, Dryopteris and Cycas all have flagellated male gametes.
Zygnema and Spirogyra reproduce by conjugation and have non-flagellated gametes.
Hydrilla and Calotropis are angiosperms, whose male gametes are non-motile and are carried by the pollen tube.
So every other set contains at least one member without flagellated male gametes, and the correct set is Riccia, Dryopteris and Cycas.
The male gametes of pteridophytes are multiflagellate (except Selaginella, which has biflagellate gametes); Dryopteris is a fern.
The male gametes of gymnosperms are generally non-motile, except those of Cycas (and Ginkgo), which are large and multiciliate.
So Riccia, Dryopteris and Cycas all have flagellated male gametes.
Zygnema and Spirogyra reproduce by conjugation and have non-flagellated gametes.
Hydrilla and Calotropis are angiosperms, whose male gametes are non-motile and are carried by the pollen tube.
So every other set contains at least one member without flagellated male gametes, and the correct set is Riccia, Dryopteris and Cycas.