Kingdom Monera: Main Features of Bacteria (NEET)

Monera contains ONLY bacteria. NCERT says it clearly: 'Bacteria are the sole members of the Kingdom Monera.' But 'bacteria' here is a big word — it includes true bacteria (eubacteria), blue-green algae (cyanobacteria), archaebacteria and mycoplasma. So even though the name sounds small, four groups sit inside it. NEET often tricks you by asking which organism is NOT a prokaryote; if it is any kind of bacteria or cyanobacteria, it IS Monera.

Yes. Every member of Monera is a prokaryote. Prokaryote means there is no true nucleus (no nuclear membrane) and no membrane-bound organelles like mitochondria or chloroplast. The DNA lies free in the cytoplasm as a single circular molecule (nucleoid). This matters for NEET because Fungi, yeast (Saccharomyces) and Protista are eukaryotes, so they are NOT Monera. A classic 2018 PYQ asks 'which is not a prokaryote?' — the answer is Fungi/yeast.

The bacterial cell wall is made of peptidoglycan (also called murein or mucopeptide). This is a NEET favourite fact. Do not confuse it with fungi (chitin), plants (cellulose) or diatoms (silica). One exception: Mycoplasma has NO cell wall at all, and it is the smallest living cell. The 2016 PYQ 'select the wrong statement' relies on you knowing bacteria cell wall = peptidoglycan is CORRECT.

Cyanobacteria are Monera, not true algae. The name 'blue-green algae' is misleading — they are actually prokaryotic bacteria, so they belong to Kingdom Monera. NCERT and a 2019 PYQ both confirm: 'Cyanobacteria are a group of autotrophic organisms classified under Kingdom Monera.' They are autotrophic (do photosynthesis) but still bacteria. Remember: word 'algae' in the name does not make it a plant.

No. Bacteria have NO true nucleus (no nuclear membrane) and NO mitochondria. Because they are prokaryotes, they lack all membrane-bound organelles. Instead of mitochondria, the respiratory enzymes sit on infoldings of the plasma membrane called mesosomes. A 2016 PYQ states 'Mitochondria are the powerhouse of the cell in all kingdoms except Monera' — and that statement is CORRECT, because Monera has no mitochondria.

Bacteria show ALL four nutrition types, which is why they are so successful. Autotrophic bacteria make their own food — either photosynthetic (using light) or chemosynthetic (using chemical energy). Heterotrophic bacteria depend on other organisms or dead matter (they are the most abundant decomposers). NCERT says most bacteria are heterotrophs. NEET trap: the statement 'Bacteria are exclusively heterotrophic' is WRONG, because many, like cyanobacteria, are autotrophs.

The single biggest difference is cell type. Monera = prokaryotic (no true nucleus). Protista = eukaryotic (true nucleus + membrane-bound organelles). Both can be single-celled, so students confuse them. But Chrysophytes, Dinoflagellates, Euglenoids, Slime moulds and Protozoans are all Protista (eukaryotes), while bacteria and cyanobacteria are Monera (prokaryotes). If it has a true nucleus, it can never be Monera.

Yes. Archaebacteria (like halophiles, thermoacidophiles and methanogens) are prokaryotes and belong to Kingdom Monera. They live in extreme habitats such as salty areas, hot springs and the guts of ruminant animals.

Yes. Mycoplasma is placed in Monera. It is the smallest living cell known and lacks a cell wall, but it still has DNA and ribosomes and is a prokaryote, so it stays in Kingdom Monera.

Because bacteria have the simplest cell structure (prokaryotic, no true nucleus, no organelles). In the NEET 2025/2026 order-of-complexity questions, Monera is placed at the lowest level of body organisation.

Bacteria mainly reproduce asexually by binary fission (one cell splits into two). Under stress they may form spores. They can also transfer DNA by a special process called conjugation, which is a kind of primitive sexual exchange.