Make sure that your figure is standing on the center of your green styrofoam field. Take your flashlight and turn it on. Gently place your flashlight on top of the blue hoop at the sunrise position. Aim the light at the figure in the center of the field. Slowly move the flashlight along the top of the blue hoop from sunrise to sunset, aiming it at the figure the entire time. Describe the change in the length of the figures shadow as you move from sunrise to noon .

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

answer: cellular respiration takes in food and uses it to create atp, a chemical which the cell uses for energy. usually, this process uses oxygen, and is called aerobic respiration. it has four stages known as glycolysis, link reaction, the krebs cycle, and the electron transport chain.