Plastids are present only in plant cells. These are of two types- chromoplasts (coloured plastids) and leucoplasts (white or colourless plastids). Plastid contains pigment called chlorophyll are known as chloroplasts. These are important for photosynthesis in plants. Chromoplasts are the organelles which provide bright colours to the plant structures like buds, flowers etc. Leucoplasts are the organelles which store starch, oils and protein granules. Plastids consist of numerous membrane layers embedded in a material called the stroma. Plastids also have their own DNA and ribosomes.
