Refers to the physical and chemical changes occurring in the body that are necessary for life.

Sally and sue were investigating the topic of friction in science. they used a small car and a ramp as seen in the picture to test what they were learning. they knew that they slipped easily on waxed floors but not on carpet, so they decided to change the material on the surface of the ramp to see what happened. they planned to use glass, carpet, aluminum foil, and sandpaper and run the car down the ramp over each surface. what would be the best research question to guide the girls' experiment? a) does the amount of surface area affect the friction on the moving car? b) will the car travel fastest on the glass surface? c) how does the angle of the ramp affect the speed of the car? d)do rougher surfaces tend to create more friction than smooth surfaces?

Which statement is the best summary of the model? a-a series of aerobic and anaerobic reactions take place in cells b- the sun's energy moves through trophic levels in a food chain c-light energy is converted into stored chemical energy plants. d- food molecules are broken down in the cells if living things.

Match the correct terms to their descriptions a system in which only energy but not matter is exchanged frozen water in snow part of geosphere that includes only soil a thin layer between the troposphere and the stratosphere cryosphere tropopause closed system pedosphere