The Five Kingdoms

• The first division of living things in the classification system is to put them into one of five kingdoms. They are:

  • Animals

  • Plants

  • Fungi

  • Protoctists

  • Prokaryotes

• Main features of all animals:

  • they are multicellular

  • their cells contain a nucleus but no cell walls or chloroplasts

  • they feed on organic substances made by other living things

A typical animal cell

Main features of all plants:

• they are multicellular

• their cells contain a nucleus, chloroplasts and cellulose cell walls

• they all feed by photosynthesis

The Animal Kingdom

• Several main features are used to place organisms into groups within the animal kingdom

Vertebrates

• All vertebrates have a backbone

  • There are 5 classes of vertebrates

Invertebrates

• Invertebrates do not possess a backbone

• One of the morphological characteristics used to classify invertebrates is whether they have legs or not

• All invertebrates with jointed legs are part of the phylum Arthropods

• They are classified further into the following classes:

Main features of all fungi (e.g. moulds, mushrooms, yeast)

• usually multicellular

• cells have nuclei and cell walls not made from cellulose

• do not photosynthesize but feed by saprophytic (on dead or decaying material) or parasitic (on live material) nutrition

Main features of all Protoctists (e.g. Amoeba, Paramecium, Plasmodium)

• most are unicellular but some are multicellular

• all have a nucleus, some may have cell walls and chloroplasts

• meaning some protoctists photosynthesise and some feed on organic substances made by other living things

Main features of all Prokaryotes (bacteria, blue-green algae)

• often unicellular

• cells have cell walls (not made of cellulose) and cytoplasm but no nucleus or mitochondria

The Plant Kingdom

At least some parts of any plant are green, caused by the presence of the pigment chlorophyll which absorbs energy from sunlight for the process of photosynthesis

• The plant kingdom includes organisms such as ferns and flowering plants

 Ferns

• Have leaves called fronds

• Do not produce flowers but instead reproduce by spores produced on the underside of fronds

Flowering plants

• Reproduce sexually by means of flowers and seeds

• Seeds are produced inside the ovary found at the base of the flower

• Can be divided into two groups – monocotyledons and dicotyledons

Viruses

Viruses are not part of any classification system as they are not considered living things

• They do not carry out the seven life processes for themselves, instead they take over a host cell’s metabolic pathways in order to make multiple copies of themselves

• Virus structure is simply genetic material (RNA or DNA) inside a protein coat