7. Type of Organism Structure Product of excretion Other features Plants Stomata, lenticels Insoluble crystals Crystals are kept inside plant cells Cnidarians and echinoderms No excretory organ - Osmoconformers, isoosmotic with environment Freshwater protists and sponges Contractile vacuole
8.
9. Flatworms Flame cells Unsegmented roundworms Protonephridia, closed network of dead-end tubes lacking openings Annelids Metanephridia, open-ended network of tubes with internal openings that collect body fluids Type of Organism Structure Product of excretion Other features
10. Molluscs Nephridia or metaphridia Crustaceans Antennal/green gland Insects Malpighian tubules and digestive tract Uric acid Type of Organism Structure Product of excretion Other features
11. Marine fishes Gills Ammonia Elasmobranchs (sharks, skates, rays) Kidneys Urea Rectal glands – excrete excess NaCl Freshwater fishes Gills Ammonia or urea Amphibians and mammals Kidneys Urea Liver converts ammonia to urea Reptiles and birds Kidneys Uric acid Salt glands Type of Organism Structure Product of excretion Other features