Bio~~~glucose

It is incorrect to say that there is no starch production at night. Starch and glucose that already exsist in the plant are interconvertible independent of light.
Photosyntheis produces glucose, not starch. Starch is produced by condensation of glucose, which can be done without the presence of light. Meanwhile, glucose can also be produced by hydrolysis of starch, also without the presence of light.

2008-02-01 15:48:53 補充：
@匿名: It would be great if you could explain how your copy-and-pasted answer relates to the original question.

夜晚光合作用會停止，只有呼吸作用。
There is no starch production @ night

Plant respiration, the enzymatic oxidation of substrates in plants, leading to the release of carbon dioxide.

Plant respiration



Plant respiration is the oxidation of certain substrates by enzymes, leading to a release of carbon dioxide. It can be loosely thought of as the opposite of photosynthesis, though the net release of carbon dioxide in respiration is less than carbon uptake in photosynthesis.
Respiration is an essential life process in plants. It is necessary for the synthesis of essential metabolites including carbohydrates, amino acids and fatty acids, as well as for the transport of minerals and other solutes between cells. It consumes between 25 and 75% of all the carbohydrates produced in photosynthesis at ordinary growth rates.


2008-02-01 19:51:42 補充：
植物日間利用光，行”光合作用”，吸入二氧化碳，呼出氧氣，夜晚植物就同人一樣，行”呼吸作用”，吸入氧氣，呼出二氧化碳，所以唔建議將植物放響房間，因為夜晚會同你爭住吸氧氣，鬥放二氧化碳．