Question

In which group of fungi, the zoospores possess two oppositely directed flagella, one whiplash and another tinsel type?
A. Ascomycetes
B. Zygomycetes
C. Oomycetes
D. Deuteromycetes

Answer 1

Hint: Several groups of fungi produce motile, flagellated asexual spores known as zoospores. These zoospores differ in number and types.

Complete answer:
Certain fungi produce zoospores at a certain stage of their life cycle and are therefore called zoosporic fungi. Flagellated fungi reproduce asexually by means of flagellated spores called zoospores that are produced in zoosporangia. The two types of flagella are whiplash and tinsel.
Tessellated flagella are also called mastigonemes. It consists of lateral hair like structures along its length called the fimmers.
Whiplash flagella are straight, and are made of three parts namely hook, filament and tip.
Some common features of zoospores-
> they are naked, wall-less cells
> they swim for many hours and then encyst by shedding their flagella
> they can respond to a range of environmental signals
Characteristics of flagellated fungi:
> They have cell walls composed of chitin, cellulose, or \[\beta \]-1,3 glucans
They obtain their nutrients by absorption.
> They possess coenocytic hyphae and reproduce via zoospores.
> They mostly inhabit on water or soil
Some of the phyla are:
> Chytridiomycota - posteriorly uniflagellate zoospores
> Hyphochytriomycota - anterior uniflagellate zoospores
> Oomycota - motile biflagellate zoospores

Therefore, the correct option is C, Oomycetes

Note: Oomycetes may occur as saprotrophs or parasites. They can be aquatic, amphibious, or terrestrial. Members of phylum Oomycota lack chitin in their cell walls and have a life cycle that is dominantly diploid. The organisms are distinguished by their production of asexual reproductive cells, called zoospores. The zoospore body of the oomycota is kidney-shaped, with a ventral groove. The two flagella emerge about one-third of the distance along this groove. The posteriorly directed flagellum is long and smooth – whiplash type while the anterior flagellum is a shorter tinsel-type. It bears tripartite hairs along its length.