Some scientists hypothesize that the first organic compounds could have been created on earth by

1 point
a.
the mixing of ocean water and soil and very low temperatures

b.
the separation of rocks and minerals over time

c.
the mixing of atmospheric gases containing ammonia, hydrogen, water, and methane at high temperatures

d.
photosynthesis that took place in primitive plants

After reading the paragraph below, answer the questions that follow. researchers have created a robot that has a very thin leg that is moved by cardiac (heart) cells contracting in unison. the robot, made of a polymer similar to that used in making contact lenses, is bathed in heart cells with supporting cells, which then attach to the robot and provide movement as they contract. all of the cardiac cells working together can cause the robot leg to move in a way that individual cells could not. this is an example of a. emergent properties of cells. b. energy flow through an ecosystem. c. adaptation. d. internal environment regulation.

Which of the following can be reduced by the use of renewable energy sources? a. social costs b. economic costs c. environmental costs d. all of the above select the best answer from the choices provided a b c d

Plants consume most of their carbon from a. the soil b. the water c. the roots d. the air