Biology · Cell: The Unit of Life · NEET
NCERT classifies plastids by the pigment they carry into exactly three types: (1) Chloroplasts, which have chlorophyll and carotenoid pigments and do photosynthesis; (2) Chromoplasts, which have fat-soluble carotenoid pigments (carotene, xanthophylls) that give yellow, orange or red colour; and (3) Leucoplasts, which are colourless and store food. For NEET, remember the basis of classification is the type of pigment.
Chloroplast is green (chlorophyll + carotenoids) and traps light for photosynthesis. Chromoplast has no chlorophyll but has carotenoids, so it looks yellow, orange or red and gives colour to flowers, fruits and old leaves. Leucoplast has no pigment at all (colourless) and its job is storage of starch, oils or protein. So the difference is pigment and function: chloroplast makes food, chromoplast gives colour, leucoplast stores food.
Xanthophyll is a carotenoid pigment, and carotenoids like carotene and xanthophyll are present in the CHROMOPLAST. This was directly asked in ReNEET 2026. Do not pick chloroplast, even though chloroplast also contains carotenoids as accessory pigments, the plastid defined by storing/showing carotenoids (carotene, xanthophyll) as its main colour is the chromoplast.
No. Plastids are found only in plant cells and in euglenoids (Euglena). Animal cells do not have plastids, cell wall or a large central vacuole. This is a common NEET trap in plant-cell vs animal-cell questions, so never tick 'plastids in animal cells'.
The AMYLOPLAST stores starch (carbohydrate), for example in a potato. Amyloplast is a type of leucoplast (the colourless storage plastids). Other leucoplasts are elaioplasts, which store oils and fats. So the chain to remember is: leucoplast is the family, amyloplast is the starch-storing member.
Yes, plastids are interconvertible. A common NEET-relevant example is a green chloroplast in a raw tomato turning into a red chromoplast when the tomato ripens (chlorophyll breaks down, carotenoids show). This is why the same fruit changes colour, the plastids convert, they are not replaced.
The plastid that stores xanthophyll is known as __________.
Match List I with List II. A. Nucleolus, B. Centriole, C. Leucoplasts, D. Golgi apparatus | I. Site of formation of glycolipid, II. Organisation like the cartwheel, III. Site for active ribosomal RNA synthesis, IV. For storing nutrients.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Plastids are classified on the basis of the type of pigment they contain: chlorophyll (chloroplast), carotenoids (chromoplast) or no pigment (leucoplast).
Plastids are found in all plant cells and in euglenoids. They are absent in animal cells. They are large enough to be seen easily under a light microscope.
Leucoplasts include amyloplasts (store starch/carbohydrate, e.g. potato), elaioplasts (store oils and fats) and aleuroplasts (store proteins).
Chromoplasts lack chlorophyll. They contain only fat-soluble carotenoid pigments like carotene and xanthophyll, which give yellow, orange or red colours to flowers, fruits and ageing leaves.
Yes. Plastids (like chloroplasts) contain their own small, double-stranded circular DNA and 70S ribosomes, which is why they are called semi-autonomous organelles.
