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Animal Kingdom. Invertebrates Animals without a backbone. All organisms in this kingdom have these common characteristics : Multicellular Eukaryotes No cell wall- unlike fungi, plants , bacteria Heterotrophs – consumers Have Specialized Cells- unlike protists. Body Plans.
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Animal Kingdom Invertebrates Animals without a backbone
All organisms in this kingdom have these common characteristics: • Multicellular • Eukaryotes • No cell wall- unlike fungi, • plants, bacteria • Heterotrophs– consumers • Have Specialized Cells- unlike • protists
Body Plans Asymmetry – no symmetry Radial symmetry - can cut in equal halves-more than one way Bilateral symmetry – allows for development of brain region in a central location (head)
Bilateral Symmetry • Has a head (dorsal) end and a Tail (caudal) end. • Has a right and left side. • Has a front (anterior) and a Back (posterior) side.
Development of Organisms Develop from a single cell, the zygote Mitosis forms new cell in a process called cleavage A hollow ball of cells are formed called a blastula Gastrulation is the folding in of the blastula to form two layers These two layers are the ectoderm and the Endoderm.
Development Ectoderm develops into skin and nervous tissue Endoderm develops into the lining of the digestive tract and organs associated with digestion In some animals the gastrula forms a mesoderm Mesoderm is the third layer and develops into muscles, circulatory, excretory, and respiratory systems
Body Cavities Acoelom- do not have a body cavity, organs are imbedded in tissues Pseudocoelom -(partial) a body cavity partly lined with mesoderm Coelom- a body cavity that provides space for the development of internal organs (something for muscles to push against to move)
PHYLUM: PORIFERA • Pore-bearing animals • sponges Phylum Porifera
Porifera Characteristics: Sessile - do not move Asymmetrical No tissue (Only organized cells – 2 cell layers) No mouth Hermaphrodite
Body plan: 2 cell layers skeleton of spicules (spines)
Sexual – release sperm into water (external fertilization very common in aquatic animals) Hermaphroditism – sponges have sperm AND eggs to increase the odds of reproduction Offspring can swim to a new location Asexual fragmentation also possible
PHYLUM: Cnidarians Stinging cell animals Jellyfish, coral, sea anemonea
Evolution of Radial Symmetry Extends tentacles equally in all directions (increase food uptake)
Characteristics: • Stinging cells • 3 cell layers • Mouth, gut for digestion • Nerve net throughout body • 2 body forms
Reproduces sexually and asexually Skeleton-none present, but dead coral remains are calcium carbonate
PHTLUM: Platyhelminthes The flatworms Planeria, tapeworms, flukes
Characteristics: No coelom – Why? Many are parasitic O2 and sugar are absorbed in host’s intestine Bilateral symmetry Reproduction-most are hermaphrodites
PHYLUM: Nematoda Roundworms hookworm, heartworms
Characteristics: • Smooth, non-segmented body • Pseudocoelom (moves more) • Can burrow through skin (walking around barefoot) • Also enters through contaminated food
Bilateral symmetry • Complete digestive system with mouth and anus • Sexual reproduction. Sexes seperate • Oxygen enters by diffusion
Hookworms, Pinworms, Tapeworms that were removed from a Brazilian boy treated on a Rockefeller foundation mission (early 1900’s) These parasites still affect people all over the globe.
Roundworms Dirofilaria is a roundworm that causes heartworm disease in dogs
PHYLUM: Annelid Segmented Worms earthworms, leeches, sea slugs
Characteristics: • Bilateral symmetry • Full Coelom (full range of motion, complex organs inside) • Complete digestion system • Most are hermaphrodites with sexual reproduction
Gets O2 directly from moist skin • closed circulatory system with 5 hearts to deliver • Food – blood (leeches), or dirt (earthworms)
Swallow dirt, filter out food Loosen soil, helps to aerate soil for plants Also fertilizes plants with castings (poop)
PHYLUM:Mollusks Head-footed animals Clams, snails, squid, oysters, octopus