Biology Chapter 3 Notes

Biology Chapter 3 Notes - Chapter 3 Water and Life Overview...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Chapter 3 Water and Life Overview: The Molecule That Supports All of Life Water is the Biological medium on Earth- All living organisms require water more than any other substance Most cells are surrounded by Water , and cells themselves are about 7095% water The abundance of water is the main reason the Earth is habitable- Figure 3.1 Concept 3.1: Polar covalent bonds in water molecules result in hydrogen bonding The water molecule is a polar molecule : the opposite ends have opposite charges- Polarity allows water molecules to form hydrogen bonds with each other Figure 3.2 Concept 3.2: Four emergent properties of water contribute to Earths suitability for life Four of waters properties that facilitate an environment for life are- Cohesive behavior- Ability to moderate temperature- Expansion upon freezing- Versatility as a solvent Cohesion of Water Molecules Collectively, hydrogen bonds hold water molecules together, a phenomenon called cohesion- Cohesion helps the transport of water against gravity in plants Adhesion is an attraction between different substances, for example, between water and plant cell walls- Figure 3.3 Surface tension is a measure of how hard it is to break the surface of a liquid- Surface tension is related to cohesion Figure 3.4 Moderation of Temperature by Water Water absorbs heat from warmer air and releases stored heat to cooler air- Water can absorb or release a large amount of heat with only a slight change in its own temperature Heat and Temperature Kinetic energy is the energy of motion- Heat is a measure of the total amount of kinetic energy due to molecular motion Temperature measures the intensity of heat due to the average kinetic energy of molecules The Celsius scale is a measure of temperature using Celsius degrees (C)- A Calorie is the amount of heat required to raise the temperature of 1 g of water by 1C Chapter 3 Water and Life The calories on food packages are actually...
View Full Document

This note was uploaded on 10/04/2011 for the course BIOLOGY 1305 taught by Professor Adair during the Fall '09 term at Baylor.

Page1 / 4

Biology Chapter 3 Notes - Chapter 3 Water and Life Overview...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online