Answer to Question 1
Increasing the concentration of greenhouse gases like carbon dioxide strengthens the greenhouse effect. As the surface of the Earth is warmed by radiation from the Sun, it emits heat energy. Greenhouse gases absorb this heat energy before it can pass through the atmosphere and back into space, raising the temperature of the atmosphere. When greenhouse gas concentrations increase, so does the temperature of the atmosphere and at the surface.
Answer to Question 2
Several thousand species are in transit every day in the ballast water of tankers and other ships. Juvenile forms of marine organisms can easily hitch rides across otherwise insurmountable oceanic barriers and set up housekeeping at distant shores. These foreign organisms-called introduced species or exotic species-sometimes outcompete native species and reduce biological diversity in their new habitats. New marine diseases can also be introduced in this way. Even canals and fishery enhancement projects can introduce potentially destabilizing new species.
The carbon-nitrogen-oxygen cycle of The Sun
The uracil-binding pocket of human UNG
A Human Element Emerges
The level of future emissions is closely linked to the rate of population growth
Structures of the Human Eye
A Short List of Human X-Linked Recessive and X-Linked Dominant Traitsa