Characteristics of Life: Properties of Water (Part 3)

Properties of Water essential abundant Cells POLAR sharing electrons III. Water – “Where there’s life…….there’s water!!” Water is the most ___________ and ____________ substance on Earth. ______are made up of mostly water and most cells are surrounded by water. The importance of water is largely due to its unique characteristics, which all directly relate to one very important property of water… Water is _________!!!! essential abundant Cells POLAR A. Polarity 1. Definition of Polarity a. The UNEQUAL __________of ___________ in molecules formed with covalent bonds. sharing electrons

Properties of Water polar hydrophilic water loving nonpolar repel 2. Hydrophilic vs Hydrophobic a. Polar molecules are attracted to other ________ molecules, and is therefore described as _______________. “Hydro” = _______, “Philic” = ________ Ex: salts, sugars b. Non-polar molecules are attracted to other ___________ molecules and will _______ polar molecules such as water. These molecules are referred to as being ________________ “Hydro” = ________ , “Phobic” = __________ Ex: fats, oils polar hydrophilic water loving nonpolar . repel hydrophobic water fearing

Properties of Water B. Water Properties – Polarity gives water some unique properties important in maintaining _______________. homeostasis sticky 1. Water is “________” - Water molecules tend to stick together, called __________ and results in ________ _________which is the measure of how difficult it is to stretch or break the surface of a liquid. Water molecules also tend to stick to other __________ – known as ___________. This explains the phenomenon known as __________ action. cohesion surface tension surfaces adhesion capillary

Properties of Water Water is the solvent of life – water dissolves many substances due to its _______. Slightly-charged ends of water molecules _______ and _________ atoms that make up other compounds, thus dissolving them. Anything dissolved in water is referred to_______. The resulting substance is known as a ________. Other _______ substances dissolve very easily in water. This is important to living systems because many important compounds in cells are in solution.   Polarity attract separate solute solution polar

Properties of Water C. _________ – tool used to measure the strength of an acid or a base, on a scale from 0-14 1. Acid – taste ____, turn litmus paper _____ (example: _______, lemon juice) 2. Base – taste ______, turn litmus paper _____, (example: cleaning products like Drain-o, _______, _____ ____.) pH Scale sour red vinegar bitter blue bleach Dish soap