he life cycle of a Zooxanthellae consist of two stages; the coccoid stage and the motile masticate phase. The most common phase in which zooxanthellae are found in the coccoid phase. In this stage, they become intercellular symbionts inside of the coral. They let go of their flagella and reproduction occurs. Zooxanthellae undergo asexual reproduction by a division called meiosis. This occurs in the dark and once the mother cell is exposed to light, it divides by cytokinesis. The two daughter cells released are two motile cells, which transitions to the other stage of their life cycle. Depending on the zooxanthellae, it determines how long they stay in this stage.
At this time, the zooxanthellae either stays inside of the coral and goes back to the coccoid stage or they leave the coral and stay in the motile phase until they enter a new coral. Corals are in charge of determining this for the zooxanthellae. They can choose whether to let go of the zooxanthellae, obtain new ones, or maintain the ones they have.
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Zooxanthellae are photoautotrophs, meaning that they perform photosynthesis using the benefits that the coral provide for them. Corals are able to provide them with carbon dioxide and water of cellular respiration. Once the zooxanthellae perform photosynthesis, they provide the coral with sugars, oxygen, and lipids. This helps the cycle continue and makes the relationship between coral and zooxanthellae symbiotic.
Via Giphy
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