CHARACTERISTICS AND CLASSIFICATION
OF KINGDOM ANIMALIA

 

CHARACTERISTICS OF ANIMALIA
 

 

Animals are a major group of organisms, classified as the kingdom Animalia or Metazoa

tickAll multicellular (metazoans) and eukaryotic

tick Ingestive heterotrophs

tick Have some type of skeletal support

tick Show levels of organization including cell, tissue, organ, and system

tick Cells are specialized for particular functions

tick Reproduce sexually

 

 


CLASSIFICATION OF ANIMALIA


Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. Scientific classification also can be called scientific taxonomy. TAXONOMY is the practice and science of classification. A TAXON (plural taxa) is a name designating an organism or group of organisms according to presumptive evolutionary (phylogenetic) relationships.

The seven main Taxa are, from largest to smallest:

KINGDOM, PHYLUM or DIVISION (botany), CLASS, ORDER, FAMILY, GENUS, SPECIES


For example: we are going to classify the bee:
 

 

bee animated gif

KINGDOM: ANIMALIA

PHYLUM: ARTHROPODA

CLASS: INSECTA

ORDER: HYMENOPTERA

FAMILY: APIDEA

GENUS: Apis

SPECIES: Apis melifera

Each species name is in Latin (scientific name) and has two parts: the genus name (in the example: Apis) and a second word identifying the species within that genus (mellifera).
Species names are usually typeset in italics. Also they may be underlined.
The genus name is always written with an initial capital letter and the specific name is never written with an initial capital.

 

 

INVERTEBRATES and VERTEBRATES


About 97% of all animals on the Earth are invertebrates. Invertebrates are any animal without a spinal column (endoskeleton). Although it is very common to separate thus the animals, this way of classification is not very correct because it classifies the animals between those that look like us (we are vertebrates and we have an spinal column), and those that do not like us (invertebrates).

However, it is used frecuently.

Characteristics of invertebrates

tick Simplest animals

tick Contains the greatest number of animal species

tick Most found in water

tick Do not have an backbone (spine column: endoskeleton).

tick Some species have an exoskeleton (Molluscs, Echinoderms) and other have no skeleton (Annelids)

tick Includes sponges, cnidarians, flatworms, roundworms, annelids (segmented worms), molluscs, arthropods, and echinoderms



 

BODY SYMMETRY IN INVERTEBRATES

Body Symmetry is the arrangement of body parts around a central plane or axis

Asymmetry: when the body can't be divided into similar sections (Porifera)

sponge


Radial symmetry: if the body parts are arranged around a central point like spokes on a wheel (Echinoderms). Most animals with radial symmetry are sessile (attached) or sedentary (move very little)

sea anemone


Bilateral symmetry: if the animals can be divided into equal halves along a single plane (right and left sides that are mirror images). Animals with bilateral symmetry are more complex, usually motile organisms, such as worms, arthropods, and all vertebrates. Animals with bilateral symmetry show cephalization (we are animals with bilateral symmetry)

crab

 

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