Kingdom Animalia Characteristics EukaryoticMulticellularHeterotrophic –ingest food Specialized cells –Most have tissues No cell wall Most motile Most sexual reproduction Diploid is dominant generation

Animals can be distinguished by determining several characteristics. Symmetry – how many lines can be drawn to divide the organism? Tissue- does the organism have tissue and how many layers? Body plan – does the organism have a coelom (body cavity) lined with tissue? Vertebrate or invertebrate – does the organism have a backbone? Skeleton – what kind of skeletal structure does the animal have? Digestion– what kind of digestive system does the animal have?

Types of Body symmetry

Types of body symmetry Asymmetry (lack of symmetry) –Ex = sponges and coral

Radial symmetry: body parts arranged around central axis –Ex = hydra and sea stars Types of body symmetry

Bilateral symmetry: body parts can be divided down a central plane –Ex = all higher organisms, humans, insects Types of body symmetry

Bilateral Symmetry Creates Complexity 95% of animals are invertebrates. There are 29 invertebrate phyla. Most have bilateral symmetry. Body orientation – dorsal (top/back), ventral (bottom/front), anterior (head), posterior (tail)

Cephalization: concentration of nerves and sensory organs at front of organism  move easily & sense danger The symmetry of an animal generally fits its lifestyle. –Many radial animals are sessile, need to meet the environment equally well from all sides. –Animals that move actively are bilateral; head end is usually first to encounter stimuli

Segmentation: Advanced/complex animals show either internal or external segmentation.

Complex Animals have tissue layers Three Potential Layers of Tissues Formed Ectoderm  outer layer Endoderm  inner layer Mesoderm  middle layer

Types of body plans Acoelomate –Has no coelom (body cavity) surrounding digestive tract –Phyla: Platyhelminthes

Types of body plans Pseudocoelomate –Has coelom surrounding digestive tract but it’s incomplete (not surrounded in mesoderm) –Phylum: Nematods

Types of body plans Coelomate –Has completely lined coelom surrounding digestive tract –Every phylum after Nematoda

Comparison of Body Plans Acoelomate Pseudocoelomate Coelomate

Invertebrate or vertebrate Invertebrates – don’t have a backbone or spinal column Vertebrates – has a backbone and/or spinal column –ONLY animals in Phylum Chordata are vertebrates! archaeopteryxsquid

Types of skeletons Exoskeleton –Ex = arthropods Endoskeleton –Ex = mammals

Skeletons Other –Ex = sponges have spicules, sea stars have spiny skin and water vascular systems

Types of digestive systems Incomplete system – (aka one opening for digestion) –Food comes in and out the same place, a mouth

Types of digestive system Complete system – (aka two openings for digestion) –Food comes in a mouth and out the anus! –Food comes in a mouth and out the anus!

Phylum Porifera- Sponges Pore-bearingSessile Body hardened by spicules Asymmetrical Contain cells only Specialized cells for digestion, filter feeders Asexual (budding) and sexual reproduction (hermaphrodites)

Phylum Cnidaria- Cnidarians Hydra, Corals, Jellies Radial symmetry Two tissue layers Incomplete digestion- carnivorous Asexual and sexual reproduction Stinging cells- nematocysts

Phylum Platyhelminthes- Flat Worms Planaria, flukes, tapeworms Bilateral symmetry 3 tissue layers Acoelomates Incomplete digestion Asexual and sexual Parasites and diseases for humans and other animals

Phylum Nematoda- Round worms Ascaris, hookworms, trichinella, pinworms 3 tissue layers Pseudocoelom Two digestive openings Separate sexes Many cause human diseases

Phylum Annelida- Segmented worms Earthworms, leeches, sand worms 3 layers: Coelom Complete digestion Asexual and sexual Circulatory System

Phylum Mollusca- Mollusks Soft body, shells Gastropods (snails), Bivalves (clams), Cephalopods (squid) 3 layers: Coelum Sexual reproduction 3 distinct body parts

Phylum Arthropoda- Arthropods Jointed appendages Classes: –Arachnida –Crustacea –Insecta 3 layers: Coelum Many: internal fertilization Exoskeleton (chitin) ¾ of all animals

Class Arachnida 2 body regions 4 pairs of legs No antennae Book lungs

Class Crustacea 2 body regions 5 pairs walking legs 3 pairs mandibles 2 pairs antennae Gills

Class Insecta 3 body regions 3 pairs walking legs 1 pair antennae Some = flight

Phylum Echinodermata- Echinoderms Spiny skin Sea stars, sand dollars, sea urchins Bilateral then radial 3 layers: Coelum CompleteRegeneration/Sexual Endoskeleton and water vascular system Tube feet

Phylum Chordata Dorsal Nerve Cord Vertebrates some stage of development Bilateral Symmetry Systems Interact Classes –Agnatha -- Chondrichthyes -- Osteichthyes –Amphibia -- Reptilia -- Aves -- Mammalia

Class Agnatha Jawless fish No scales Long and slender Ectotherm- external temp. regulation

Class Chondrichthyes Cartilaginous fish Tooth-like scales Paired fins Ectothermic Internal fertilization (give birth to live young) Their bone structure is actually cartilage

Class Osteichthyes Bony fish Scales Paired fins Air Bladder 2 chambered heart External fertilization Ectothermic

Class Amphibia Amphibians Life in water/on land Gills then lungs 3 chambered heart Ectothermic

Class Reptilia Reptiles Dry skin, scales Amniotic egg LungsEctothermic

Class Aves Birds Endothermic: body temp. regulated by homeostasis 4 chambered heart Feathers=modified scales

Class Mammalia Mammals Mammary glands Internal development HairEndothermic

Class Mammalia