The Greek word Symbioum means live together. The close co-existence of two organisms of different species that benefit from each other is called mytosymbiosis. Algae Zoochlorella and green hydra Chlorohydra viridissima form mitotic organisms. Again, sea urchins and clownfish form a symbiotic relationship. Algae parts are transmitted to the next generation along with hydra eggs. So algae is called lifelong paying guest. How hydra and algae benefit is discussed below.Dr. Siddiq Publications
How Algae Benefit
1. Shelter: Algae take shelter in hydra’s endodermal muscle cells.
2. CO2 Acquisition: Algae use the CO2 produced in hydra respiration for photosynthesis.
3. Nitrogen acquisition: The nitrogenous waste products of hydra metabolism are used by algae to produce carnivorous food.
4. Protection from environmental stress: Algae take shelter in hydra’s body. So it is protected from heat, stress, dryness etc. Dr. Siddiq Publications
How does Hydra benefit?
1. Food: Hydra consumes excess food produced by algae in the process of photosynthesis. When the algae die, the corpse is used by the hydra as food.
2. Obtaining O2: Hydra uses the O2 produced by algae in the process of photosynthesis. Dr. Siddiq Publications
3. Excretion of waste products: Hydra produces nitrogenous waste products in the process of respiration. Algae consume these waste materials and free the hydra waste.