The plastids developed as the so called proplastids.

质体转变为所谓的原质体。

Usually, plants perform photosynthesis by way of tiny organelles called plastids.

通常，植物是靠一种叫做叶绿体的纤小细胞器完成光合作用的。

The slugs digest most of the algae, but those plastids remain whole and undigested.

海藻的大部分被这种海蛤蝓消化，但是叶绿体保持完整不被消化。

Regulation of foreign gene expression in plastids is influenced by various factors.

外源基因在质体中的表达调控受多种因素影响。

The SEs were rich in mitochondria, P type plastids, and some SEs had nacreous wall.

筛分子内有较丰富的线粒体、P 型质体，有些筛分子有珠光壁。