What is a component of the plasma membrane that creates a chemical barrier between the inside and the outside of the cell?

An enzyme lowers the energy of activation. what does that mean?

Identify the examples in which sam interacts only with natural resources

Describe the change in phase and temperature as water moves from the oceans to the atmosphere and then returns to earth again as rain. a) evaporation : temperature increases; condensation : temperature decreases; precipitation (rain) : temperature decreases b) evaporation : temperature increases; condensation : temperature decreases; precipitation (rain) : temperature increases c) evaporation : temperature decreases; condensation : temperature decreases; precipitation (rain) : temperature decreases d) evaporation : temperature increases; condensation : temperature increases; precipitation (rain) : temperature decreases