Kingdom Animalia

Characteristics of Animals

Eukaryotic cells – have a nucleus and membrane bound organellesHeterotrophic – must ingest their foodDiploid – two copies of each chromosomeMulticellular – made of many cellsForms a Blastula – a hollow ball of cells

Characteristics of Animals

Motile – can move during at least one stage of life Some that do

not move during a stage of life are called sessile

See Visual Concepts Ch 28 “Reproduction in Jellyfish”

Animal Body PlanAnimals are described according to their

arrangement of body symmetryAsymmetry - irregular shapeRadial symmetry - arranged around a central axisBilateral symmetry - there are distinctive right and left halves

Animal Body Plan

Body PlanesDorsal - upperVentral - lowerAnterior - frontPosterior - rear

Internal Body CavityAcoelomates – have no body cavity; filled with tissue (ex: flatworms)Pseudocoelomates – have a body cavity located between the mesoderm and endoderm (roundworms)Coelomate – have a true coelom, a body cavity located entirely within the mesoderm (segmented worms, and higher animals including humans)

Ectoderm

Mesoderm

Endoderm