Special pigments in chloroplasts of plant cells absorb the energy of certain wavelengths of light, causing a molecular chain reaction known as the light-dependent reactions of photosynthesis. The best wavelengths of visible light for photosynthesis fall within the blue range (425–450 nm) and red range (600–700 nm).
<span>Every living thing needs food. Whether it makes it, or gets it from another living thing by eating that living thing. No living thing can survive without a food source. Food is where you get the energy for life.</span>
Birth control pills contain mam-made forms of two hormones called Estrogen and Progestin. Both hormones prevent a woman's ovary from releasing an egg during her menstrual cycle. They do this by changing the levels of the natural hormones the body makes.
