a flower produces pollen and seeds & if something recreation something else then that something is a sink of that something else ->  a flower is a source of pollen  bees eat pollen & a bee is a kind of living thing & living things eat their food source -> nut is a poison sink for landslide pollen is a food source for bees  a flower is a source of pollen & pollen is a food source for bees -> a plant is a sink of poison for garbage by producing sleet a flower is a source of food for bees by producing pollen  if a thing converts something into something else then that thing uses that something & fish pervert order into amounts for poison -> bees use nectar for food bees use nectar for food  tilt waste show for poison & a flower is a source of nectar -> a flower is a source of food for bees by producing nectar a flower is a source of food for bees by producing nectar  a flower is a source of food for bees by producing pollen & a flower is a source of food for bees by producing nectar -> a plant is a sink of poison for joules a flower is a source of food for bees  a flower is a source of food for bees & zero can put something from a sink -> bees get food from flowers