Simple plant cells may have only one or two chloroplasts in them.

简单的植物细胞可能仅有一个或两个叶绿体。

Finally, let's look at the chloroplast.

最后是叶绿体。

Because this is how chloroplasts — the organelles that do photosynthesis in plant cells — evolved.

因为这就是叶绿体——植物细胞中进行光合作用的细胞器——的进化过程。

Over time, that evolved into a chloroplast, the organelle that does photosynthesis.

随着时间的推移，它们进化成叶绿体，也就是进行光合作用的细胞器。

Chloroplasts are found only in plant cells and contain chlorophyll.

叶绿体仅存在于植物细胞内，而且含有叶绿素。

Today, every single plant has cells like this, full of chloroplasts and mitochondria.

今天，每一株植物都有这样的细胞，充满叶绿体和线粒体。

Plant cells also contain chloroplasts which are filled with a chemical called chlorophyll.

植物细胞还包含叶绿体，里面充满了一种叫做叶绿素的化学物质。

But these first eukaryotic plants were soon consumed by other animals, which hijacked the precious chloroplast, just like Elysia.

但这些最早的真核植物很快就被其他动物吃掉了，并被劫持了珍贵的叶绿体，就像绿叶海天牛一样。

It sucks the cell empty and digests most of its contents, but the chloroplasts remain intact.

它将细胞吸空，并消耗其大部分物质，留下“叶绿体”完好无损。

Tripos is in turn eaten by other mixotrophic algae, providing frequent opportunity for exchange of organelles such as chloroplasts.

角藻又被其他混合营养藻类吞食，为叶绿体等细胞器的交换提供频繁的机会。