Plastid

A plastid is a self-reproducing organelle of plants and algae. A plastome is the DNA genome of a plastid.^[1]p341 They are like tiny machines inside cells: each makes or stores important chemicals used by the plant.

Examples of plastids are:

• Chloroplasts: photosynthesis; other plastids may have developed from chloroplasts. Etioplasts are chloroplasts which have not been exposed to light.
• Chromoplasts: pigment synthesis and storage.
• Leucoplasts: colourless, make terpenes such as resin. Sometimes they develop into more specialized types of plastid:
  • Amyloplasts: starch storage
  • Elaioplasts: fat storage.
  • Proteinoplasts: store & modify protein.
    • Statoliths: detect gravity.

1. ↑ King R.C. Stansfield W.D. & Mulligan P.K. 2006. A dictionary of genetics, 7th ed. Oxford.