A keystone species helps define an entire ecosystem. Without its keystone species, the ecosystem would be dramatically different or cease to exist altogether.
Transforms water, carbon dioxide, and minerals into oxygen and organic compounds.

[b] The sporangia are knob-like structures.
They are present at the top of the thread-like structures called hyphae.
They are dispersive, i.e. they are scattered by rain, wind or insects.
Answer:
Asexual reproduction can be described as a process in which daughter cells are produced which are 100% identical to the parent cells. Unlike the process of sexual reproduction, no recombination occurs in asexual reproduction. Hence, no variability is produced when organisms reproduce by this method.
<u><em>As there will be lack of variability in asexual reproduction, the whole of the particular species might become endangered or extinct due to a disease or due to other factors like pests.</em></u>
<u><em></em></u>