Question

Zygospore is formed from
A) Gametangial copulation
B) Gametic union
C) Zygote
D) Oogamy

Answer 1

Hint:Haploid gametes are found in algae and fungi which fuse to form a diploid zygote. for producing sporophyte it does not germinate immediately. A thick wall is secreted around to form a resting spore and zygospore. In unfavourable conditions it undergoes a resting period. In favourable conditions if the organism shows alternation of generation it germinates to produce a diploid sporophyte.

Complete answer:
Zygospores are asexual spores of zygomycetes. Zygospore are tough and resistant spores that are formed by fusion of two nuclei of the two haploid cells and form gametangia to produce zygote and after it the zygospore. In the zygospore the diploid nucleus undergoes meiosis to produce haploid zoospore in plants where alternation of generation is not present. Zoospore germinate to produce haploid plants.
Mitospores are nonmotile and called sporangiospores as the spores are formed inside sporangia born at the tips of sporangiospores. Sexual reproduction occurs through conjugation. The product of sexual reproduction is diploid spores and zygospores. For example Rhizopus stolonifer or black bread mould.

Hence the correct answer is option ‘A’.

Note:Sexual reproduction takes place by conjugated neighbouring hyphae which produce sporangium after a resting period.when sporanium becomes mature it bursts to release spores which germinate on meeting favourable conditions.The grayish black colour of the mould develops due to formation of sprangium which release dark coloured spore which are scattered by wind and germinate after falling out a suitable place.this is asexual reproduction.