Classification of living things

Why do we need to classify living things? There are over 1.4 million different

species of discovered organisms on earth. We classify them to make studying them easier.

Organisms are divided into five large groups called kingdoms.

kingdoms

animals plants Bacteria fungi protoctists

Animals

Plants

Bacteria

Fungi

Protoctists

We still find that in each group there may be organisms that are very different such as ants and

giraffes in the animal kingdom. That is why each kingdom is divides into smaller

groups called phyla (singular: phylum). Each phylum is divided into several classes, then a

class is divide into orders, then family, then genus and finally the smallest group is called species.

Kingdom>phylum>class>order>family>genus>species.

Try to remember them using this sentence: King Philip cut oranges for good students.

Animal kingdom Animals are either vertebrates (have a

back bone) or invertebrate (without a back bone).

Vertebrates are divided into five classes.

vertebrates

Fish Amphibians Reptiles

Birds

Mammals

Fish Amphibians Reptiles Birds Mammals

Body covering

Limbs

Ears

Eggs

Other features

Insects Arachnids Crustaceans Myriapods

Body segments

Number of legs

Antenna

Other features

Common features They all have: 1. Segmented bodies 2. Jointed legs 3. A hard exoskeleton

Molting in insects

Other invertebrates Annelids Nematodes Molluscs

Annelids

nematodes

Molluscs

Molluscs

tentacles

Flowering plants Monocotyledons Dicotyledons

monocotyledons

Dicotyledons