Lions Tigers and Bears Diff Biology April 15
Lions, Tigers, and Bears… Diff. Biology April 15, 2005
Kingdom Animalia • There are 9 phyla that we will look at. – Porifera (sponges) – Cnidarians (jellyfishes) – Platyhelminthes (flatworms i. e. tapeworms, planarians) – Nematoda (roundworms i. e. pinworms, hook worms). – Mollusca (mollusks i. e. clams, snails, squid)
Phyla Continued – Annelida (annelids i. e. earthworms) – Arthropoda (arthropods i. e. spiders, millipedes) – Echinodermata (echinoderms i. e. starfish, sand dollars, sea urchins) – Chordata (chordates) • Invertebrates – lancelets and tunicates • Vertebrates – fish, birds, amphibians, reptiles, and mammals.
Just the Facts… • Eukaryotic, Multicellular • Well developed tissues • Usually motile • Heterotrophic by ingestion • Sexual reproduction • Diplontic life cycle • Respond to stimuli
How are they classified? • Type of level of organization; ecto, meso, and • • • endoderm germ layers Symmetry; Radial/Bilateral Body plan; sac plan/tube-within-a-tube plan Type of coelom - – Acoelomates (mesodermal lining absent) – Psuedocoelomate (incomplete lining of mesoderm) – True coelomates (complete lining of mesoderm in the internal body cavity) *see page 626 • Presence of segmentation
Proto vs. Deutero • Protostome: during embryonic development the first opening is the mouth. • Dueterostome: during embryonic development the first opening is the anus and the mouth is second.
Invertebrates • Sponges are asymmetrical • Cnidarians have radial symmetry • All other phyla have bilateral symmetry. • Annelids show segmentation, both internally • and externally. Arthropods display an exoskeleton. Within this phyla nervous systems are beginning to become more complex, along with circulation and respiration.
Invertebrates Con’t • Echinoderms – – – deuterostomes enterocoelomates internal skeleton internal organs radial symmetry water vascular system
Vertebrates - Chordates • An animal must have the four given traits listed below – A dorsal supporting rod called a notochord. – A dorsal hollow nerve cord – Pharyngeal pouches (these are seen during development and may become gills, auditory tubes, tonsils, thymus) – Tail
Vertebrates • Two invertebrate chordates – Lancelets and Tunicates, this is because the notochord is never replaced with a vertebral column.
Vertebrates • Vertebrates are distinguished by these traits in particular: – Living endoskeleton – Closed circulatory system – Paired appendages – Efficient respiration and excretion – High degree of cephalization
The Top Five • Fish • Amphibians • Reptiles • Birds • Mammals
Here fishy, fishy… • Three classes of fish – – – Jawless (hagfish and lampreys) Cartilaginous (sharks and rays) Bony (trout, bass, most abundant) • Bony skeleton and scales • Swim bladder • Paired fins • Jaws • Gills
Ribbit, Ribbit…. • Amphibians (Amphibia) frogs, toads, newts, and • • • salamanders Usually tetrapods Metamorphosis involved with development Three-chambered heart Usually lungs in adults Smooth, moist skin Reproduction occurs in water, but the animals can live on land.
Reptilesssss. • Reptiles (Reptilia) Snakes, lizards, turtles, • • • alligators Usually tetrapods Lungs with expandable rib cage Shelled egg Dry, scaly skin Cold blooded (ectothermic) Internal fertilzation
Pretty Bird… • Birds (Aves) chickens, penguins, eagle • Usually wings for flying • Hard-shelled egg • Four-chambered heart • Feathers • Air sacs • Endothermic • Well developed brain (instinctive behavior i. e. migration)
Mammals • Mammals (Mammalia) • There are three types of mammals – Monotremes: which lay shelled eggs (i. e. duckbilled platypus) – Marsupials: young are born immature and develop in the mother’s pouch (i. e. koala, kangaroo) – Placental Mammals: young develop internally
Mammals • Body hair • Differentiated teeth • Infant dependency • Constant internal temperature • Mammary glands • Well-developed brain • Internal development
Mammals All of these different traits are made to help the animal be more successful on land. Mammals are essentially considered terrestrial organisms, meaning they live on land, but this doesn’t mean they never live in water, a whale for example.
Heads up for next week! Next week you all will be creating your own organism. So over the weekend look over the various traits of the animals and become familiar with them so you can answer questions about it when you present them.
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