BIOL 111 Lecture Notes - Lecture 3: Hydrogen Bond, Surface Tension, Plant Cell
Document Summary
3/4 of the earth"s surface is submerged in water. Abundance of water is the main reason earth is habitable. Living organisms made mostly of water and live in an environment dominated by water. Water is only common substance to exist in natural environment in all 3 physical states of matter. Structure of water molecule allows it to interact with other molecules. Polar molecule: the overall charge is unevenly distributed: partial negative charge ( -) near oxygen and a partial positive charge ( +) at the. Polarity allows water molecules to form hydrogen bonds with each other. 4 properties of water: cohesive behavior, ability to moderate temperature o. Expansion upon freezing: versatility as a solvent. Cohesion helps transport water against gravity in plants. Adhesion: attraction between different substances, for ex. between water & plant cell walls. Surface tension: measure of how hard it is to break the surface of a liquid.
