Two students, Renu and Rohit, were having a discussion on the plastids. Class 9

Two students, Renu and Rohit, were having a discussion on the plastids. Class 9

Question 1.

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. Class 9

Answer:

Rohit is partially correct, but Renu is more accurate overall.

Rohit is right that roots do not perform photosynthesis since they are underground and do not receive sunlight, so chloroplasts are indeed absent in root cells.

However, Renu is correct that plastids are still present in roots - just not chloroplasts. Roots contain leucoplasts, which are colourless plastids that store food materials like starch, oils, and proteins. Leucoplasts do not need light to function - their job is storage, not food synthesis. A well- known example is potato and taro roots, where leucoplasts store large amounts of starch.

So the key point is that plastids are not limited to chloroplasts alone. There are three types of plastids - chloroplasts, chromoplasts, and leucoplasts - and not all of them require sunlight or perform photosynthesis. Roots contain leucoplasts, which makes Renu's broader statement correct: all parts of a plant, including roots, do contain plastids, just not the same type.