Chapter 4: Animal Kingdom - Basis of Classification

A set of vocabulary flashcards covering the fundamental features and levels of organisation used in the classification of the animal kingdom.

Classification

The process that helps in assigning a systematic position to newly described species and is essential due to the description of $\text{over a million}$ species of animals.

Basis of Classification

Fundamental features common to individuals such as arrangement of cells, body symmetry, nature of coelom, and patterns of digestive, circulatory, or reproductive systems.

Cellular level of organisation

A pattern of organisation where cells are arranged as loose cell aggregates, as exhibited in sponges.

Tissue level of organisation

A more complex arrangement of cells where cells performing the same function are grouped into tissues, as seen in coelenterates.

Organ level of organisation

A level of organisation where tissues are grouped together to form specialised organs for particular functions, exhibited by members of Platyhelminthes and other higher phyla.

Animalia

A kingdom where all members are multicellular, though they exhibit different patterns of cell organisation.

Sponges

Animals that exhibit a cellular level of organisation with some division of labour (activities) occurring among the cells.

Coelenterates

A group of animals in which the arrangement of cells is more complex than in sponges, exhibiting a tissue level of organisation.

Platyhelminthes

A phylum whose members exhibit a higher level of organisation known as the organ level.