Inclusion Bodies in Prokaryotic Cells: Meaning, Examples and Why They Are Not Membrane-Bound
Biology · Cell: The Unit of Life · NEET
Inclusion bodies are stores of reserve (food) material kept in the cytoplasm of prokaryotic cells like bacteria. The most important NEET point: they are NOT surrounded by any membrane and they lie free in the cytoplasm. Examples are phosphate granules, cyanophycean granules and glycogen granules. Memory hook: "Free food, no wrapper" - they store food but have no membrane wrapper.
Inclusion bodies (phosphate, cyanophycean and glycogen granules) lie free in the bacterial cytoplasm without any membrane, storing reserve material. They do not ingest food.
Your doubts, answered
Are inclusion bodies membrane-bound or not?
They are NOT bound by any membrane. This is the single most tested fact. NCERT says clearly: inclusion bodies are not bound by any membrane system and lie free in the cytoplasm. So if a NEET option says inclusion bodies are membrane-bound, it is wrong.
What are the examples of inclusion bodies (the ones NEET asks)?
Learn exactly three from NCERT: (1) phosphate granules, (2) cyanophycean granules, and (3) glycogen granules. NEET options often list these three, so memorise them as a group. Trick to remember: 'P-C-G' = Phosphate, Cyanophycean, Glycogen.
What do inclusion bodies actually store or do?
They store reserve material, meaning stored food or energy the cell can use later. For example glycogen granules store carbohydrate, phosphate granules store phosphate. They do NOT take in or digest food from outside. A common NEET trap says inclusion bodies help in 'ingestion of food particles' - that is false.
Are inclusion bodies the same as gas vacuoles?
No. Both are found in prokaryotes, but they are different. Inclusion bodies store reserve food (phosphate, cyanophycean, glycogen granules). Gas vacuoles help the cell float and are found in blue-green, purple and green photosynthetic bacteria. Do not mix the two lists.
Do eukaryotic cells have inclusion bodies like these?
In NEET NCERT, inclusion bodies (phosphate, cyanophycean, glycogen granules that lie free and unbound) are described as a feature of prokaryotic cells. For your exam, treat 'reserve material stored free in cytoplasm as inclusion bodies' as a prokaryotic point.
Why does the 'no membrane' point matter for NEET?
Prokaryotic cells have very few membrane structures. A big theme in this chapter is that prokaryotes lack membrane-bound organelles. Inclusion bodies fit this theme: they store material but without any membrane. So NTA loves to test whether you know they are NOT membrane-bound.
⚠️ The NEET trap ✗ Inclusion bodies are involved in ingestion of food particles. ✓ Inclusion bodies only STORE reserve material (like glycogen or phosphate) inside the cytoplasm; they do not take in or ingest food from outside. Ingestion of food is done by food vacuoles/phagocytosis in some eukaryotes, not by inclusion bodies. 🧠 They HOLD food, they do not EAT food - storage only, no ingestion.
Real NEET questions
NEET 2020
Which of the following statements about inclusion bodies is not correct?
A · They lie free in the cytoplasm
B · These represent reserve material in cytoplasm
C · They are not bound by any membrane
D · These are involved in ingestion of food particles ✓
Solution: Inclusion bodies are reserve materials stored free in the cytoplasm of prokaryotic cells and are not bound by any membrane, so options A, B and C are correct descriptions. They do NOT ingest food particles, so statement D is incorrect. NCERT: 'Reserve material in prokaryotic cells are stored in the cytoplasm in the form of inclusion bodies. These are not bound by any membrane system and lie free in the cytoplasm, e.g., phosphate granules, cyanophycean granules and glycogen granules.'
NEET 2017
Select the mismatch.
A · Gas vacuoles - Green bacteria
B · Large central vacuoles - Animal cells ✓
C · Protists - Eukaryotes
D · Methanogens - Prokaryotes
Solution: Large central vacuoles belong to plant cells, not animal cells, so B is the mismatch. Gas vacuoles are correctly found in green (photosynthetic) bacteria, protists are eukaryotes, and methanogens are prokaryotes. This PYQ tests that you can pair prokaryotic cytoplasmic features (like gas vacuoles) with the right cells, alongside inclusion bodies.
Solved Cell: The Unit of Life NEET PYQs
Try the real previous-year questions from this chapter — each with the answer and a full solution.
