Question

There is symbiotic algae in the secretory cells of Hydra. It is

• A. Nostoc
• B. Anabaena
• C. Zoochlorellae
• D. All of the above

Answer 1

The correct option is C Zoochlorellae

Green Hydra (Hydra viridissima) contains in its gastrodermal myoepithellial cells, the endosymbiotic unicellular green algae and forms a stable symbiosis. Endosymbiotic algae in freshwater invertebrates are commonly named Zoochlorellae. The term Zoochlorellae was given by Brandt (1882), who described the green bodies - coccoid unicellular Chlorella, which includes also endosymbiotic algae. Zoochlorellae is used as a generic term, that covers all green algae, that form endosymbiotic associations in freshwater invertebrates.

Thus, the correct answer is option C.