Question

By which of the following methods an alga can perennate under unfavorable conditions?
A. Zoospores
B. Palmella stage
C. Akinete
D. Both B and C

Answer 1

Hint: The freshwater and subaerial algae are unprotected and regularly exposed to the danger of desiccation and extremes of temperature. Marine algae sleep in conditions where variations in external environmental conditions of life are rare but still, they're exposed to tidal fluctuations.

Complete answer:
Algae is a crucial group of organisms that are found during a wide selection of habitats be it oceans, rivers, freshwater lakes, ponds or brackish water bodies, snow, barks of the trees, etc. starting from a little tiny cell to the enormous Kelp measuring up to many meters, these plants have some unique features that aren't found in the other group of organisms.
Algae have both Prokaryotic and Eukaryotic groups, large sorts of pigment systems, triphasic life cycle, an extended evolutionary history, etc. Algae changed the planet’s atmosphere by producing oxygen thus paving the way for the evolution of life on earth. These tiny organisms not only give us oxygen to breathe, food to eat, medicines to heal, cosmetics to use but also provide tons of data about the origin of life. It's been predicted that future vehicles will run on algal biofuels and power plants will use algae for water sequestration.

Hence correct option is (D).

Note: Zoospore may be a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some algae, bacteria, and fungi to propagate themselves. The best methods of perennation in freshwater and subaerial algae are akinetes, aplanospores, palmella stage, cysts, oospore, homosporous, Hypnos pores, and tubers.