The Animal Kingdom!

What is an Animal???• What do all these things have in common??

What is an animal?• Eukaryotes• Multi-cellular• Have no cell walls• Heterotrophs – that usually ingest (take in)

and then digest their food• Usually mobile or have ability to move in at

least one stage of their lives• Reproduce sexually and produce an embryo

that undergoes stages of development

Phylogenetic tree of the Animal Kingdom

Major divisions among Animal PhylaCharacteristics used to classify animals:1 a) Has nerves, tissues, and 2 or 3 germ layers.............. Go to 2 b) No nerves, no tissues, only 2 germ layers ...Phylum Proifera

(Sponges) Nerves = specialized cells used to coordinate movements and sense changes in the environment

Germ layer = layers of cells in the embryo that give rise to specific tissues in adults

Major divisions among Animal Phyla2 a) Body plan exhibits bilateral symmetry ..... Go to 3

b) Body plan only exhibits radial symmetry ..Phylum Cnidaria (e.g. Corals, jellyfish, sea anemones)

Radial symmetry = a body plan that has symmetry around a central axis

Bilateral symmetry = a body plan that has symmetry around a midline (only divides along one plane)

Major divisions among Animal Phyla3 a) Animals with a coelom...................... ..... Go to 5 b) Animals without a coelom........................ Go to 4

Coelom = a fluid-filled body cavity that provides space for the development and suspension of organs and organ systems

Major divisions among Animal Phyla4 a) No coelom (acoelomates)..... ..... P.

Platyhelminthes (Flatworms)

b) Pseudocoelomates........... P. Nematoda (Roundworms)

Major divisions among Animal Phyla5 a) Protostomes ............................. ..... Go to 6 b) Deuterostomes ............................... Go to 8

Protostome = during embryonic development, the mouth forms before the anus

Deuterostome = during embryonic development, the anus forms before the mouth

Major divisions among Animal Phyla6 a) Segmented body...................... ..... Go to 7 b) Unsegmented body ................ P. Mollusca (e.g.

Snails, clams, squid)

Major divisions among Animal Phyla7 a) Segmented body, no jointed appendages...P.

Annelida (e.g. Earthworms) b) Segmented body, jointed appendages .............

P. Arthropoda (e.g. Insects, spiders, lobsters, centipedes)

Major divisions among Animal Phyla8. a) Have Vertebrae ............................ P. Chordatab) No Vertebrae ..........................P. Echinodermata

Vertebrate = an animal with a backbone or a notochord

Notochord = a flexible, rod-shaped structure found in some chordates; generally gets replaced by vertebrae during embryonic development

invertebrate = an animal without a backbone – note: most animals are invertebrates!

TASK Using the chart on pg. 104 and 105 in hand out, create

a dichotomous key for chordate classes.

Read pg. 97 – 107

Answer Questions: 1, 2, 5, and 11.