Biology·Core Principles

Kingdom Fungi — Core Principles

NEET UG
Updated 21 Mar 2026

Core Principles

Kingdom Fungi comprises eukaryotic, heterotrophic organisms that absorb nutrients from their environment. Their cell walls are made of chitin, distinguishing them from plants (cellulose) and animals (no cell wall).

Most fungi are filamentous, forming hyphae that collectively make up a mycelium, though some are unicellular (e.g., yeast). They reproduce vegetatively (fragmentation, budding), asexually (spores like conidia, zoospores, aplanospores), and sexually (involving plasmogamy, karyogamy, and meiosis, often with a dikaryophase).

Fungi are classified into Phycomycetes (aseptate, coenocytic, zoospores/aplanospores, zygospore), Ascomycetes (septate, conidia, ascospores in ascocarps, prominent dikaryophase), Basidiomycetes (septate, basidiospores on basidia in basidiocarps, long dikaryophase), and Deuteromycetes (imperfect fungi, only asexual reproduction by conidia known).

They are crucial decomposers, symbionts (lichens, mycorrhizae), and pathogens, with significant ecological and economic importance.

Often confused with

Side-by-side differences the NEET paper likes to test.

Kingdom Fungi vs Kingdom Plantae
AspectKingdom FungiKingdom Plantae
Cell Wall CompositionChitin (primarily)Cellulose (primarily)
Mode of NutritionHeterotrophic (absorptive)Autotrophic (photosynthetic)
Presence of ChlorophyllAbsentPresent
Food StorageGlycogenStarch
Body OrganizationMostly filamentous (hyphae, mycelium), some unicellularMulticellular, differentiated tissues and organs (roots, stems, leaves)
MotilityGenerally non-motile, except for some zoosporesNon-motile (sessile)

Fungi and Plants, though both eukaryotic, represent distinct kingdoms with fundamental differences. Fungi are heterotrophic decomposers with chitinous cell walls and store food as glycogen, while plants are autotrophic producers with cellulose cell walls and store food as starch.

The absence of chlorophyll in fungi and their filamentous body plan further distinguish them from the complex, differentiated structures of plants. These differences highlight their separate evolutionary paths and ecological roles.

Why it is tested: NEET relevance: Understanding these distinctions is crucial for correctly classifying organisms and for answering conceptual questions that compare and contrast different kingdoms. Questions often test the unique features of fungi that set them apart from plants, such as cell wall composition, nutritional mode, and storage products.