Metazoa Flashcards
“Meta” means _____ and “Zoa” means ______
“Complex” ; “Life Form”
There are over ______ formally described species in Metazoa
2 million
How many major phyla for animals
35
Most Metazoa are
Arthropods
Less than 5% of Animals are
Vertebrates
Opisthokonts
Eukaryotes with a posterior flagella
Closest single celled relative to Metazoa are
Choanoflagellates
Choanoflagellates
Closest living relatives of animals
8 Key Features of Metazoans
-multicellular
-cellular differentiation
-cell to cell communication
-heterotrophic
-motile
-homeostasis
-diploids (meiosis at reproduction)
-embryonic stage
Heterotrophic
Nutrients are derived from other organisms
Choanocytes occur in
Sponges
Simplest animal are the
Sponges
Animal Phylogenetic Relationships are determined by 4 factors
-comparative morphology
-comparisons of embryology
-fossil record
-molecular sequence alignments
Molecular comparison reveals similarities between
Choanoflagellates and Animals