Which is a form of active transport? proteins push molecules through the cell membrane. proteins create openings on another side of the cell membrane. proteins open up channels in the cell membrane. proteins enter and exit the cell freely.

Which contributions did galileo make to the model of the solar system? check all that apply. a mathematical model for the orbits of the planets scientifically accurate data on planetary orbits data that showed that planets reflected sunlight similar to earth's moon up the idea that stars are other suns that do not move u observations of the moons of jupiter rotating around the gas giant