After it reaches its maturity, the whole volume of the oil cell is filled with the large vacuole, which becomes the oil sac subsequently.

当油细胞发育成熟后，细胞质及核开始解体，整个油细胞的腔由大液泡充满，成为油囊。

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Biodiesel can be produced by extracting the oil from the algae cell.

BBC: Bath's Roman Baths algae could fuel cars

Siemens and Shell, for example, have just announced a new fuel-cell technology for oil rigs that will capture emissions of carbon dioxide and methane, generate power from them cleanly, and sequester the exhaust.

ECONOMIST: Emissions

The research team are therefore also looking for a species of algae with a weaker cell wall and high oil content.

BBC: Bath's Roman Baths algae could fuel cars