Act 17: Respiratory and Circulatory System of Vertebrates

• Respiratory and circulatory system in vertebrates can be invaginated or evaginated.
• Fish - evaginated
• Operculum - bony plate covering the gills
• Gills - The organs that allow for gas exchange in aquatic animals.
• Gill arches - supports gills
• Gill filaments - inside the gill arches is a set of this
• Gill rakers - filters water
• Lamellae - supports gill filaments main network responsible for gas exchange
• 3 respiratory surface of frog: skin, lungs, and lining of mouth
• Toads have invaginated systems
• Mucus glands in skin keep it moist
• Inspiration - air drawn in mouth
• Expiration - air forced out
• Larynx is connected to two bronchi connected to the lung
• Gas exchange occurs in capillaries.
• 3 parts of circulatory system: heart, blood, and blood vessels.
• Circulatory system of vertebrates are closed type
• Fish - 2 chambers
• Amphibians - 3 chambered heart
• Mammals, Birds, Crocodile - 4 chambered hearts
• Chambers of heart: atrium and ventricle.
• Blood vessels: veins, arteries, capillaries
• Capillaries - smallest blood vessel
• Plasma - nutrient containing
• Lymph fluid - keeps moisture
• RBC (erythrocytes) - where O2 binds
• WBC (nymphocytes) - immune systen
• Platelets (thrombocytes) - blood clotting
• Arteries - carry blood away the heart
• Veins - bring blood back to heart
• In toad the heart is contained in the pericardium.
• Atrium - inflow
• Ventricle - outflow
• Sinus venosus - closes vein to heart attached to the vein