Arthropods

1.

Life Cycle

Most undergo metamorphosis (egg -> larva -> pupa -> adult)

Some reproduce parthenogenetically (a form of asexual reproduction whereby offspring are produced without the embryo being fertilised by a male).

Complex mating rituals in some groups

2.

Structure & Characteristics

-Segmented body with jointed appendages (legs, antennae, mouthparts)

Bilateral symmetry

Compound eyes and other sensory organs

Exoskeleton made out of chitin

3.

Nutrition

Subclasses

1. Chelicerata (Arachnids)

-Examples: Spiders, scorpions, ticks, mites

-Chelicerae (pincers/fangs) as feeding appendages

-Book lungs or tracheae for respiration

2. Crustacea

-Examples: Crabs, shrimp, lobsters, barnacles

-Mostly aquatic

-Two main body sections

3. Hexapoda (Insects)

-Examples: Ants, butterflies, beetles

-Three body parts: head, thorax, abdomen

-Six legs, often winged

-Most successful and widespread group