Vertebrate Origins Haikouella lanceolata early Cambrian Diversity of

Vertebrate Origins Haikouella lanceolata, early Cambrian

Diversity of Chordates American toad, Bufo americanus 56, 000 species 10 mm to 40 m long Every habitat Large body size Pronghorn antelope, Antilocarpa americana Sea squirt, Atriolum robustum Laughing gull, Larus atricilla Shoal chub, Macrhybopsis hyostoma Eastern box turtle, Terrapene carolina Amphioxus (probably Branchiostoma)

Endostyle-thyroid Chordate Characteristics 1. 2. 3. 4. 5. Notochord Pharynx Dorsal, hollow nerve cord Postanal tail Endostyle-thyroid gland

How are vertebrates different from other chordates? 1. ENDOSKELETON: Vertebrae? (actually vertebrae are lacking in hagfishes and rudimentary in lampreys) 2. Cephalization: Cranium (all sense organs located towad anterior region o body) 3. Tripartite 4. brain with associated complex, paired sense organs and cranial nerv Chambered heart: CLOSED circulatory system 5. Alimentary canal (digestive system) 6. Specialized organ systems

Body Systems • Integumentary – Hair, skin, nails, sweat glands and sebaceous glands – Protection – Regulates body temperature – Houses sense organs

Body Systems • Muscular – – – Muscles FXN: causes body movement maintains posture produces body heat

Body Systems • Skeletal – Bones, cartilage, ligaments – Aids in movements – Support – Protects – Produces blood cells

Body Systems • Digestive System – Mouth, tongue, teeth, salivary glands, esophogus, stomach, liver, sm and lg intestines – Breakdown food and absorbs nutrients – Excretes waste

Body Systems • Respiratory – Lungs and nasal cavity, bronchi – Exchange gases

Body Systems • circulatory – Heart and blood vessels – Transports blood and nutrients thru body

Body Systems • Excretory/ urinary – Kidneys, urinary bladder, urethra – Removes waste from blood – maintain water balance – eliminates urine

Body Systems • Endocrine – Pituitary glands, pancreas thyroid, adrenal gland – Secrete hormones to regulate metabolism

Body Systems • Nervous – Brain, spinal column, sense organs – Respond to stimuli Animation: http: //health. howstuffworks. com/adam -200011. htm

Body Systems • Reproductive – Vagina/Penis – Reproduction – Support dev of embyro