Transcript Kingdom Animalia

Kingdom Animalia
Invertebrates to Vertebrates
General Characteristics
• Multicellular eukaryotes
• Heterotrophs that ingest their food
• Mostly sexual reproduction, some
asexual
• Controlled Movement – response via
nerve impulses & muscle coordination
Invertebrates vs. vertebrates
•
Evolution
• 800 MYA from motile protists that
liked to hang out together
–choanoflagellates
• Movement from water to land
– protection from dessication & sun’s
rays
Move from water to land
determines changes in…
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Body support & movement
Reproduction
Circulatory system
Respiratory system
Digestive and excretory system
Nervous system
Common morphology
• 3 categories of morphology for
classification and evolutionary
advances
–Symmetry
–Germ layers
–Body cavity
symmetry
Advantages of bilateral symmetry
– Allow for cephalization
• Centralized nervous system in a head
– Allows for segmentation
• Specialization of body parts
– Allows for one way digestive system
• Input (eating) to output (excretion) that
flows in one direction vs. a 2-way
system
Germ layers
• Ectoderm
-becomes hair, skin, nervous system
• Mesoderm
-becomes skeleton, muscle, inner skin,
circulatory system, liver
• Endoderm
– becomes gut and associated organs,
lungs, gills, pancreas, and their
linings
Body Cavity
• Acoelomate
–Solid organism
–restricted movement &
function
• Psuedocoelomate
–False body cavity
Body Cavity, cont’d
Coelomate
– True body cavity – body cavity surrounded by
mesoderm
– Allows for ease of mobility & function, i.e.
digestion, circulation
– More room for larger organs (or coiled organs)
so processes can take longer/efficiency
– Allows for retention of eggs/gametes
• Internal fertilization (protects young)
Patterns of Development
• Type of cleavage determines whether
or not cells can regenerate and ease of
cloning
Patterns of Development
• Indirect
–Metamorphosis
through a life
cycle
vs.
Direct
-growth &
differentiation
Earliest animals sponges
• Phylum Porifera
• Collection of cells, able to
communicate with each
other
• No true tissue layers
• No symmetry or organs
• Sessile, suspension feeders
• O&D
• regeneration
First true animals
• Phylum Cnidarian
– Jellies, anemones, hydra,
corals
• Phylum Ctenophora
– Comb jellies
– 2 (?) true tissue layers but
lacking in complex systems
– Sexual reproduction
– Radial Symmetry
Early Worms
• Phylum Playthelminthes
– flatworms
• Phylum Nematoda
– Round worms
Phylum Mollusca
• 1st with true coelum
• The “head-foods”
• Radula
Phylum Annelida
• Earthworms (segmented worms)
• Hermaphrodites
• Do NOT regenerate!!
Phylum Arthropoda
• Largest phylum, essential for evo. Of plants
• Exoskeleton limits size
– Crayfish, insects, lobsters, spiders
– Jointed appendages
Phylum Echinodermata
• First deuterostomes, closely related to us
• Starfish, sea urchins
– “Spiny skin”
Phylum Chordata
• Dorsal nerve chord
• Notochord
• Pharyngeal (gill)
slits
• Post-anal tail
– Classes – birds,
reptiles,
amphibians,
mammals