Chordate Characteristics

Urochordates Tunicates & Sea Squirts

Cephalochordates Lancelets (Amphioxus)

Agnatha Hagfish & Lamprey

Agnatha - True vertebrae - Gills

Lamprey

Chondrichthyes (cartilagenous fish)

Gnathostomes

2 chambered heart

Cat Shark Egg Oviparous Porbeagle embryo viviparous Dogfish Shark embryos Ovoviviparous

Lateral Line

Osteichthyes

Osteichthyes Bone in their skeleton An operculum covering the gill openings A swimbladder or lungs True scales Paired fins Ammonia excretion

Amphibia Amphibians 1st tetrapods

Tetrapod Ectothermic 3-chambered heart (Double circulation) Smooth skin, lacks scales (Desiccation if dry) Cutaneous respiration Lungs Excretes urea

Metamorphosis Tadpoles Frogs Herbivorous Carnivorous Aquatic Aquatic & Terrestrial Single loop circulation Double loop circulation Gills Lungs

External Fertilization

Bioindicators

Reptile Characteristics Ectothermic Dry skin covered in scales Most have 2 pairs of short legs & clawed feet Oviparous reproduction Internal fertilization – to avoid desiccation of gametes

Eggs amniotic Lungs to breathe 3 or 4 chambered heart No metamorphosis Hibernate & aestivate

Excretory Waste The excretory waste of the reptiles is uric acid

Aves Endothermic Feathers = modified scales Wings Hollow bones 4 chambered heart Amniotic egg Parental care Crop & gizzard Air sacs & lungs Counter-current circulation Uric Acid excretion Aves

Parental Care

Mammals Endothermic Mammary glands Fur 4 chambered heart Diaphragm

Monotremes

Marsupials

Eutherians