slide 1 of 5. A polygenic trait, is a trait that nonallelic genes control. These traits result from one or more genes contributing to the phenotype. An individual's physical appearance is determined by chromosomal inheritance and genotypic ratio. This phenomenon is known as Mendel's Laws of Inheritance.
, cycle. Water molecules continuously move from location to location in this cycle. The water cycle is important to weather and climate and, ultimately, to all life on Earth. The water cycle is driven primarily by the energy from the sun. This solar energy drives the cycle by evaporating water from the oceans, lakes, rivers, and even the soil. Other water moves from plants to the atmosphere through the process of transpiration.
Water Cycle Water can exist either as a solid (ice), a liquid (water), or a gas (water vapor). Water on the on surface of Earth is constantly changing between these three states. Ice can change to become water or water vapor. Water can change to become ice or water vapor. Water vapor can change to become ice or water. These continuous changes in state create a cycle of repeating events. Water continually circulates between the surface of Earth and its atmosphere in what is called the hydrologic or water cycle.