What does a seed cleaner do?

What are the experiments to prove that microorganisms are presented in air? Why do some people needing a kidney transplant do not get one? What planets atmosphere had belts of clouds? Where do greater sage grouses live? Is the blue penguin an omnivore a carnivore or a herbivore? Why don't many asteroids hit the earth? Tissue vs organ vs organ system? What does rust coloured water in the radiator mean? Is a high pressure area of tightly packed molecules? The thickest sedimentary deposits are found? How many kilograms are in 1 pound? What generalization can be made about functioning ecosystem? How can we tell mars is covered with red rocks? What is Leaves a compound mixture or element? Is there a foliage tree that is called the burning bush that makes its own compost to feed other trees? Is the island Krakatau a product of primary or secondary succession? What is the dense center portion in a nucleus in a cell? Which component in the fire triangle will raise the temperature to the flash point? Can foam rubber sheets be used for insulation? Why are blind sharks called blind?