• Plastids are species specific or region specific. They bear some specific pigments, thus imparting specific colours to the plants.

• Based on the type of pigments plastids can be classified into chloroplasts, chromoplasts and leucoplasts.

• The chloroplasts impart green color as they contain chlorophyll and carotenoid pigments which are responsible for trapping light energy essential for photosynthesis.

• The chromoplasts contain fat soluble carotenoid pigments like carotene, xanthophylls and others are present. This gives the part of the plant a yellow, orange or red colour.

• The leucoplasts are the colourless plastids of varied shapes and sizes with stored nutrients: Amyloplasts store carbohydrates (starch), e.g., potato; elaioplasts store oils and fats whereas the aleuroplasts store proteins.