Derek Shirlaw

Derek Shirlaw | Biology | Life

A state of being that seperates living organisms from inorganic objects.

Derek Shirlaw | Biology | Cells

Often referred to as being the building blocks of life, cells are the structural and functional units of all known living organisms.

Derek Shirlaw | Biology | Genetics

The study of heredity and variation in living organisims, and the basic units of inheritance known as genes.

Derek Shirlaw | Biology | Minibeasts

Generally, small animals without a backbone. Minibeasts are invertebrates - the most numerous type of animal in the World!

It’s estimated that in Britain alone, there are more than 25,000 different species of invertebrates! An invertebrate lacks an internal skeleton making them soft and flexible. Some have shells to protect their soft bodies, whilst others have a hard exo-skeleton.

Because there are so many species, Scientists classify different Minibeasts into smaller groups according to their characteristics. The largest group are the arthropods; Arthropods are characterised by the possession of a segmented body with appendages, such as jointed limbs, on at least one segment:

Insects e.g. beetles, butterflies, ants, dragonflies, cockroaches, ladybirds

Arachnids e.g. spiders, mites, scorpions

Myriapods e.g. centipedes, millipedes

Crustaceans e.g. crabs, lobsters, woodlice

Insects are by far the most numerous of the arthropods with a staggering 22,450 identified species living in Britain alone. To qualify as an insect, an animal must have 6 legs and a body divided into 3 parts – a head, a thorax and an abdomen.

There are a further four classes of Minibeasts:

Molluscs e.g. snails, slugs, mussels, octopuses, squid

Annelids e.g. earthworms, flatworms, leeches

Coelenterates e.g. jellyfish, sea anemones, corals

Echinoderms e.g. starfish, sea urchins

Although Minibeasts are generally small, some species, such as jellyfish, octopuses and squid can grow to be quite sizeable, their soft bodies supported by their watery environment.