VERTEBRATES

YOU MUST KNOW… THE FOUR CHORDATE CHARACTERISTICS TRAITS WHICH DISTINGUISH EACH OF THE FOLLOWING GROUPS: CHONDRICHTHYES, OSTEICHTHYES, AMPHIBIA, REPTILIA, BIRDS, AND MAMMALIA ADAPTATIONS THAT ALLOWED ANIMALS TO MOVE ONTO LAND HOW THE THREE CLASSES OF MAMMALS DIFFER IN THEIR REPRODUCTION

CONCEPT 34.1 CHORDATES HAVE A NOTOCHORD AND A DORSAL, HOLLOW NERVE CORD

VERTEBRATES ARE MEMBERS OF THE PHYLUM CHORDATA 4 CHARACTERISTICS NOTOCHORD – APPEARS DURING EMBRYONIC DEVELOPMENT BETWEEN THE DIGESTIVE TUBE AND THE DORSAL NERVE CORD DORSAL, HOLLOW NERVE CORD – FORMED FROM A PLATE OF ECTODERM THAT ROLLS INTO A HOLLOW TUBE PHARYNGEAL CLEFTS – GROOVES THAT SEPARATE A SERIES OF POUCHES ALONG THE SIDES OF THE PHARYNX. THEY ALLOW WATER TO ENTER AND EXIT THE MOUTH WITHOUT GOING THROUGH THE DIGESTIVE TRACT A MUSCULAR TAIL POSTERIOR TO THE ANUS

CONCEPT 34.3 VERTEBRATES ARE CRANIATES THAT HAVE A BACKBONE

LAMPREYS OLDEST LINEAGE OF VERTEBRATES, JAWLESS PARASITIC FISH WITH A SKELETON OF CARTILAGE

CONCEPT 34.4 GNATHOSTOMES ARE VERTEBRATES THAT HAVE JAWS

JAWS EVOLVED FROM MODIFICATION OF THE PHARYNGEAL (GILL) SLITS CLASS CHONDRICHTHYES – FLEXIBLE ENDOSKELETONS COMPOSED OF CARTILAGE, STREAMLINED BODIES, DENSER THAN WATER, WILL SINK IF THEY STOP SWIMMING – SHARKS AND RAYS CLASS OSTEICHTHYES – BONY FISHES, COVERED WITH SCALES, POSSESS A SWIM BLADDER – TROUT AND SALMON

CONCEPT 34.5 TETRAPODS ARE GNATHOSTOMES THAT HAVE LIMBS AND FEET

CLASS AMPHIBIA – INCLUDE FROGS, TOADS, SALAMANDERS, AND NEWTS GAS EXCHANGE CAN OCCUR ACROSS THEIR THIN, MOIST SKIN – MAY HAVE LUNGS MAY HAVE AQUATIC LARVAL STAGE WITH GILLS AND METAMORPHOSIS TO AN ADULT (FROGS) HAVE EXTERNAL FERTILIZATION AND EXTERNAL DEVELOPMENT IN AN AQUATIC ENVT (EGGS WITHOUT SHELL) AS LARVAE, AMPHIBIANS HAVE A TWO-CHAMBERED HEART (1,1). AS ADULT, THREE-CHAMBERED HEART (2,1).

CONCEPT 34.6 AMNIOTES ARE TETRAPODS THAT HAVE A TERRESTRIALLY ADAPTED EGG

AMNIOTES CONSIST OF MAMMALS AND REPTILES (ALSO BIRDS) AMNIOTIC EGG WAS IMPORTANT EVOLUTIONARY DEVELOPMENT FOR LIFE ON LAND EGGS HAVE SHELL THAT RETAINS WATER SO IT CAN BE LAID IN DRY ENVT EGG HAVE AMNION (FLUID), CHORION, ALLANTOIS, AND YOLK SAC (GAS EXCHANGE, WASTER STORAGE, AND TRANSFER OF STORED NUTRIENTS)

REPTILES – TURTLES, LIZARDS, SNAKES, ALLIGATORS, CROCODILES, EXTINCT DINOSAURS MODERN REPTILES HAVE SCALES CONTAINING KERATIN (REDUCE WATER LOSS) OBTAIN OXYGEN THROUGH LUNGS ECTOTHERMIC (REGULATE TEMP THROUGH BEHAVIORAL ADAPTATIONS RATHER THAN METABOLISM) INTERNAL FERTILIZATION AND AMNIOTE SHELLED EGG NITROGENOUS WASTE IS URIC ACID HEART IS THREE-CHAMBERED (2,1)

BIRDS – WINGS, FEATHERS, ADAPTATIONS FOR FLIGHT LAY AMNIOTIC EGGS HAVE KERATIN-CONTAINING SCALES ON THEIR LEGS LIGHT, HOLLOW BONES, FEWER ORGANS FEATHERS AND A LAYER OF FAT INSULATES BIRDS FOUR-CHAMBERED HEART, HIGH METABOLISM ENDOTHERMS – MAINTAIN A WARM, CONSISTENT BODY TEMP

CONCEPT 34.7 MAMMALS ARE AMNIOTES THAT HAVE HAIR AND PRODUCE MILK

MAMMALS POSSESS MAMMARY GLANDS HAVE A BODY COVERING OF HAIR HAVE A FOUR-CHAMBERED HEART ARE ENDOTHERMIC INTERNAL FERTILIZATION, ARE BORN PROPORTIONALLY LARGER BRAINS THAN OTHER VERTEBRATES ALL HAVE TEETH OF DIFFERING SIZE AND SHAPE

MONOTREMES – EGG LAYING MAMMALS THAT HAVE HAIR AND PRODUCE MILK – PLATYPUSES, ANTEATERS MARSUPIALS – BORN EARLY IN DEVELOPMENT AND COMPLETE EMBRYONIC DEVELOPMENT IN A POUCH WHILE NURSING – KARGAROO, OPOSSUM PLACENTAL MAMMALS (EUTHERIANS) – LONGER PREGNANCY, COMPLETE THEIR DEVELOPMENT IN THE UTERUS – DOGS, HUMANS

HUMANS BELONG TO THE ORDER PRIMATES ALONG WITH MONKEYS AND GORILLAS OPPOSABLE THUMBS, LARGE BRAINS AND SHORT JAWS, FORWARD-LOOKNG EYES, FLAT NAILS, WELL-DEVELOPED PARENTAL CARE, COMPLEX SOCIAL BEHAVIOR HUMANS – INCREASED BRAIN VOLUME, SHORTENING OF JAW, BIPEDAL POSTURE, REDUCED SIZE DIFFERENCE BETWEEN SEXES