|MadSci Network: Botany|
It is a very interesting question. Actually in research, a chloroplast is not difficult to extract. Following extraction, photosynthesis does not take place, even though there are light reactions that occur. I think this would not be changed even if all the necessary enzymes were present.
There are at least two reasons for this:
Firstly, the chloroplast is a complex organelle, not only in terms of structure, but also in terms of genetics. Some of photosynthesis function genes are encoded by chloroplast itself, but the organelle genes are encoded in nucleus. This due to the probable evolutionary origin of chloroplast, which is believed to have arisen from a symbiotic association between a photosynthetic bacterium and a non-photosynthetic eukaryotic organism. So chloroplasts cannot replicate independently.
Secondly, although most of the photosynthetic process take place in the chloroplast, there are some processes in other organelles, such as mitochondria. For many kinds of plants, photosynthesis is finished cooperatively in different cells. This means photosynthesis is a process for multiple organelles together, thus it is regulated by complicated cellular metabolism, not only several enzymes.
In a word, based on our current knowledge and techniques, people still cannot make photosynthesis happen independently outside of a plant cell.
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