What are the importance of leeches?

Why do silkworms only eat mullberry leaves? How do you get rid of mosquito bites in 5 hrs? What are haemoprotozoans? What advantage is the difference in the shape of an earthworm and two ends? True or false one of the main contributions of bees to mankind is the pollination of plants? What is a shiny green beetles name? How long does it take for locust thorns to decay? is a flea a forager, grazer, filter feeder, predator, scavenger, or a parasites? Where is a spiders abdomen? What did early Chinese do to control pest? What is like stable and corral? How do stick insects reproduce? Why does the caterpillars moult several times? What is as the insects gathering the nectar it will rub again? What are those little yellow bugs that bite you when you cut the grass? Which organism would get the least amount of energy in a food chain plant -worm-bird-man? How do worms help us? Do human have worns in their bodies a friend told me she saw worms in her stool.? How much does a girl spider crab weight? What is The small worm-like outgrowth at the end of the cecum called?