The interaction is seemingly neutral for one of the organisms. For example, a barnacle attached to a whale can travel thousands of miles collecting and filtering food from the moving water. The whale doesn't seem to be affected by the little hitchhikers.
The statement presented above that is not true about paper recycling is; A) Recycling one ton of newspaper can save 100 trees.
Paper recycling are the processes of reprocessing waste paper such as old newspapers and magazines into new paper products for reuse. Apart from saving trees from being cut, paper recycling has many other significant benefits such as reducing water and air pollution, saving on the use of water resources and energy.
For every ton (200 pounds) of newspaper that is recycled, 17 trees are saved.
The answer is C. We can suppose that the Grey gene is "A" and Black gene is "a". So the gene of heterozygous grey fruit fly is "Aa", and the black-bodied fruit fly is "aa". After mating, the offspring can get only "a" from balck-bodied fruit fly and has equal opportunity to get a "A" or "a" from heterozygous grey fruit fly. If the gene of offspring is "Aa", it will be grey. If "aa", it will be black. So the proportion of being black is 0.5.
Plants showing hydrotropism grow in response to water.
