Two students, Renu and Rohit, were having a discussion on the plastids. Renu emphasised that all parts of the plants, even roots, contain plastids. However, Rohit did not agree with the statement and told her that plastids are absent in plant roots since the roots are underground and do not need to perform photosynthesis. Who is correct? Justify your answer.

Renu is correct. Plastids are present in roots, but they are mainly storage plastids rather than photosynthetic plastids. In green parts of the plant, such as leaves, plastids are mainly chloroplasts, which contain chlorophyll and carry out photosynthesis. In roots, which are generally underground and do not receive sufficient light, plastids are usually colourless leucoplasts. These leucoplasts, especially amyloplasts, store food materials such as starch. Therefore, plastids are present in roots, but they do not usually function in photosynthesis.