Niveditha

Monera

Examples: Bacteria, blue-green algae (cyanobacteria)Key Features:

• Organisms are prokaryotic — no true nucleus or membrane-bound organelles.

• Usually unicellular (some form colonies).

• Reproduce asexually by binary fission.

• Nutrition can be autotrophic (photosynthetic/chemosynthetic) or heterotrophic.

• Cell wall composition varies; many have peptidoglycan.

Why it matters:Monerans were the earliest forms of life and are crucial for nitrogen fixation, decomposition, and biotechnology.

Protista

Examples: Amoeba, Paramecium, Euglena, algaeKey Features:

• Eukaryotic but simpler than plants, animals, or fungi.

• Mostly unicellular; some are colonial or simple multicellular.

• Show great diversity in movement: pseudopodia, cilia, or flagella.

• Can be autotrophic, heterotrophic, or mixotrophic.

• Live in aquatic or moist environments.

Why it matters:Protists are considered the "link" between prokaryotes and more complex eukaryotes; they essentially form the evolutionary bridge to plants, animals, and fungi.

Fungi

Examples: Yeast, mushroom, mouldsKey Features:

• Eukaryotic and predominantly multicellular (yeast is unicellular).

• Heterotrophic by absorption (saprophytic, parasitic, or symbiotic).

• Cell wall made of chitin.

• Body usually composed of thread-like hyphae forming a mycelium.

• Reproduce by spores (sexual or asexual).

Why it matters:Fungi are key decomposers, recyclers of nutrients, and sources of antibiotics and food (like mushrooms and bread yeast).

Plantae

Examples: Mosses, ferns, gymnosperms, flowering plantsKey Features:

• Eukaryotic, multicellular, and autotrophic (photosynthetic).

• Possess chlorophyll; cells have a cell wall made of cellulose.

• Show a high level of tissue differentiation.

• Life cycles often include alternation of generations.

Why it matters:Plants produce oxygen, form the base of most food chains, and maintain the balance of gases in the atmosphere.

Animalia

Examples: Sponges, insects, mammals, reptiles, fishKey Features:

• Eukaryotic, multicellular, and heterotrophic.

• Cells lack cell walls.

• Highly specialized tissues, organs, and organ systems.

• Most show locomotion at some stage of life.

• Reproduction is usually sexual.

Why it matters:Animals include the most complex organisms on Earth and play essential roles in ecosystems, including pollination, seed dispersal, and maintaining population balances.

Quick Kingdom Comparison

• Monera: Prokaryotic, unicellular.

• Protista: Eukaryotic, mostly unicellular.

• Fungi: Eukaryotic, heterotrophic by absorption, chitin cell wall.

• Plantae: Eukaryotic, multicellular autotrophs, cellulose cell wall.

• Animalia: Eukaryotic, multicellular heterotrophs, no cell wall.