Download BIO NOTES #207D- CH03- ANIMALS - TJ

CHAPTER 3:
PRODUCTS
OF
EVOLUTION:
UNITY &
DIVERSITY
KINGDOM ANIMALIA
• Characteristics– Eukaryotic
– Multicellular (with no cell wall like plants)
• Cell specialization- forming tissue
• Leads to higher level functions
– Heterotrophic through ingestion
– Sexual reproduction and development
– Movement and coordination
KINGDOM ANIMALIA
• Two main categories
– Invertebrates (without a backbone)
– Vertebrates- Chordates (with a
backbone)
• Criteria used to classify
– Symmetry
– Germ or tissue layers
– Body cavities
INVEREBRATES
• 8 major phyla
– Classification based on
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embryonic development,
symmetry,
germ layers, and
body cavity
– 97% of all animals are invertebrates
– All lack a backbone
PHYLUM PORIFERA
(pore bearer)
• SPONGES- simplest animals
– Asymmetrical
– Little tissue specialization
– No germ layers
– No true coelom (body cavity)
– Sexual and asexual reproduction
– Most are sessile (not mobile) in
adulthood
PHYLUM CNIDARIA
• Radial symmetry
• Two germ (cell) layers
– Epidermis
– gastrodermis
• Simple organ systems
• Three Classes of Cnidaria
– Class Hydrozoa- hydra, man-of-war
– Class Scyphozoa- jellyfish
– Class Anthozoa- sea anemones, coral
PHYLUM MOLLUSCA
• Characteristics
– 2nd most diverse phylum of animal
– Have a true coelom
• Fluid filled cavity that is completely surrounded by
mesoderm
• Separates the gut from epidermis
• Allows a space where the circulatory, muscular, and
eventually skeletal systems develop
– Body plan
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Bilaterally symmetrical
Head-foot region- contains the mouth and a foot for moving
Visceral mass region- contains internal organs
Mantle- epidermis that secretes shell
PHYLUM MOLLUSCA
• THREE MAIN CLASSES
• Class Gastropoda- snails, slugs, etc.
– One or no shell
– Foot is near the gut
• Class Bivalvia- clams, oysters, scallops
– Two shells
– No distinct head, but big foot
• Class Cephalopoda- squid, octopuses
– Feet (tentacles) near the head
– No shell (except for the nautilus)
– Chromatophres- pigments for color change
• Squids- 10 tentacles
• Octopuses & other cephalopds- 8 tentacles
PHYLUM ANNELIDA
• Characteristics
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Segmented Worms
Bilaterally Symmetrical
True coelom
Simple organ systems
• Digetive- esophagus, crop, gizzard
• Circulatory- aortic arches
• Nervous- ventral nerve cord
– Setae- external bristles
– Parapodia- some have fleshy protrusions that are
‘like-feet’
• Three Main Classes
– Class Oligochaeta- common earthworms
– Class Polychaeta- bristle worms
– Class Hirudinea- leeches
PHYLUM ARTHROPODA
• Most diverse phylum of animals
• Characteristics
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Bilaterally symmetrical
True coelom
Segmented bodies
Jointed appendages (extensions)- ‘arthropods’
Exoskeletons
High degree of cephalization- head developmentantennae & mouth parts
– Compound eyes- made up of many small eyes
– Molting- shedding exoskeleton & growing new
one
3 SUBPHYLA OF ARTHROPODA
• Subphylum Crustacea- Crustacians
– Crabs, lobsters, shrimp, crayfish, pill bugs
• Characteristics
– Mostly aquatic
– Two major body sections• Cephalothorax & abdomen
– Two pairs of appendages on the head
– Five pairs of walking legs
• One pair of appendages on each other body segment
• Subphylum Chelicerata
– Class Arachnida- spiders, scorpions, horseshoe crabs
• Characteristcs
– Terrestrial
– Two major body sections• Cephalothorax & abdomen
– Two pairs of appendages on the head
– Four pair of walking legs- all on thorax
SUBPHYLUM UNIRAMIA
• Class Diplopoda- millipedes
– Two pairs of legs on each body segment
• Class Chilopoda- centipedes
– One pair of legs on each body segment
• Class Insecta- ¾ of all animal species
– Entomology- study of insects
– 15 major orders of insects
• Lice, termites, dragonflies, grasshoppers, beetles, flies, bees,
ants, butterflies, fleas
• Characteristics–
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Mostly terrestrial
Three body segments- head, thorax, & abdomen
Three pairs of walking legs on the thorax
One or two pairs of legs
Exoskeleton
Dorsal aorta
Spiracles and tracheae for respiration
Digestive system with crop and stomach
Ventral nerve cord
PHYLUM ECHINODERMATA
• Characteristics
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Radially symmetrical (mostly penta-radially
Bilaterally symmetrical larvae
Endoskeleton
Water vascular system
Tube feet
• Examples
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Starfish
Sea lillies
Brittle stars
Sea urchins
Sea cucumbers
PHYLUM CHORDATA
SUBPHYLUM VERTEBRATA
• Characteristics
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Dorsal hollow nerve cord
Vertebral column to protect nerve cord
Cranium to protect the brain
Bilaterally symmetrical
True coelom
Endoskeleton
Highly developed nervous system & brain
Highly developed senses
• 7 Major classes of vertebrates
– Class Agnatha- lampreys & hagfish
• No jaws
– Class Chondrichthyes- sharks & stingrays
• Cartilaginous skeletons
• Placoid scales
• Olfactory bulbs- good sense of smell
– Class Osteichthyes- All bony fish
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Bone skeleton
Swim bladder
Scales
Four chambered heart- linear
– Class Amphibia- frogs, toads, salamanders
• Aquatic larval stage
• Moist, thin skin with no scales
• Three chambered heart
• 7 Major classes of vertebrates
– Class Reptilia- snakes, lizards, turtles, crocodiles
• Lay eggs
• Dry, scaly skin
• Three chambered heart
– Class Aves- birds
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Lay eggs
Feathers
Wings
Beak
Four chambered heart
– Class Mammalia- us, dogs, cats, bears, sheep, horses,
rhinoceri, elephants, cows, rats, etc.
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Endothermy- internal body heat
Hair
Four chambered heart
Milk- mammary glands
Placental birth
– Kangaroos have pouches- marsupials
– Duckbill platapus lays eggs- monotreme