different types of plastids with different functions

-chromoplast: coloured by carotenoids

-leucoplasts: without pigments, storage of various substances

-chloroplast: photosynthesis

-etioplast: colourless (develop in absence of light)

-amyloplast: starch storage

plastids can be transformed from one form to another

they are produced by division of plastids but cannot develop from any other source