Introduction:
Life on Earth is amazingly diverse.
In order to make it simpler to study and describe life, scientists have devised a system of classifying living organisms. All living organisms can be classified into one of five groups, called kingdoms.
- Taxonomy: study of the classification of living organisms.
The five kingdoms of life
Monera:
Monera: all bacteria – the most numerous organisms, as well as having the greatest biomass, on Earth.
Protista:
Protista: small single-celled organisms such as Amoeba, Cryptosporidium and algae (such as seaweeds).
- They are all aquatic-based
- Some are autotrophic (e.g. algae); some are heterotrophic (e.g. Amoeba)
- Some are multicellular (e.g. seaweeds); some are single celled (e.g. Amoeba)
- Some reproduce asexually (e.g. Amoeba); some reproduce sexually (e.g. seaweeds)
Fungi:
Fungi: single-celled or multicellular heterotrophic organisms such as yeasts, moulds and mushrooms.
- They all possess chitin in their cell walls
- They are all heterotrophic
- They all reproduce by means of spores – by producing the spores either by asexual or sexual reproduction
Plantae:
Plantae: Multi-cellular photosynthetic organisms.
- They are all multicellular
- They are all photosynthetic
- They all have cellulose in their cell walls
- They all have vacuoles for storage in their cells
- They can reproduce asexually or sexually
Animalia:
Animalia: Multi-cellular heterotrophic organisms.
- They are all multicellular
- They are all heterotrophic
- They all reproduce sexually
