Transcript AMPHIBIANS
AMPHIBIANS Kingdom: Animalia Phylum: Chordata Animals with a backbone Phylum Chordata • Classes: – Amphibia – Reptilia – Aves – Chondrichthyes – Osteichthyes – Mammalia General Characteristics • It is an animal in Kingdom Animalia, Phylum Chordata, Class Amphibia • Most lay eggs in WATER. • It is an ECTOTHERM – body temperature is determined by environment (opposite = Endotherm) Salamander vs. Newt Which one is an amphibian? What’s the difference? • Toad vs. Frog Life Cycle • Begin life as an Egg mass (Eggs are Moist, not Hard) • Go through Metamorphosis • Egg to Tadpole to Tadpole frog to Young frog to Adult frog • External Fertilization Respiratory System • Begin their lives with gills and most end their lives with lungs. • Some can breathe through their skin – their skin is permeable (allowing materials to flow in the frog to out of frog) • So…how does the oxygen get in our blood? Let’s take a look at Humans… • 4 chambered heart • Very efficient • Let’s label… – – – – – – – – – Right ventricle Left ventricle Right Atria Left Atria Aorta To lungs (not oxygenated) From lungs (oxygenated) To body (oxygenated) From body (not oxygenated) Cardiovascular System • Frogs have a 3 chambered heart • Consisting of 2 atria and 1 ventricle. • Lungs help to oxygenate the blood and also take out carbon dioxide Digestive System • • • • • • • • • Mouth – break down of food Gullet Esophagus Stomach – break down of food Small intestine – food is digested and absorbed Liver makes bile; gall bladder stores bile Pancreas secretes enzymes to break down food Large intestine – water is absorbed Cloaca – excretes exit Digestive System • Accessory organs help to digest food • Liver – makes bile • Gall bladder – stores bile • Pancreas – secretes enzymes to help with digestion Excretory System • Kidneys – remove toxins from blood • Toxins travel through the ureter (tube) until it reaches the bladder. • Bladder holds the urine until it is excreted through the cloaca. Importance • Amphibians help us to monitor the environment • Check the handout for more information Frog Malformations