Because the recessive trait might not show, but its there, lets say B is brown eyes and b is blue eyes, BB is brown, Bb is brown, and bb is blue, if B is present, brown will always show, but as long as the little b is there, there is a chance of the kids having blue eyes, sure most people would have brown eyes, but a lot of the people with brown eyes would be Bb
Theories basic to all of the life sciences include the cell theory because all living things are made up of cells.
B. tears , this is not a first line of defense
A tree's mass is mainly biomass. During photosynthesis plants, the carbon is used to transform the Sun's energy into chemical energy that is captured in the bonds of carbon molecules made of atmospheric carbon dioxide and water