Unit 1
-man is high 50’s to 60% water
-distribution in body divided into 3 compartments:
1) intracellular - 28 litres
2) intercellular/interstitial fluid - 11 litres - 80%
3) blood plasma - 3 litres - 20%
-women contain less water than men
-organisms can contain 60-80% water
-bacteria have lots of water
-fat cells have little
-water’s properties result from its structure and molecular interactions
-water is polar
-polar covalent bonds and asymmetrical shape give it opposite charges on
opposite sides
-electrons spend more time around O giving H a slight positive charge
-hydrogen bonds form between the oxygen of one molecule and the
hydrogen of another
-cohesion: substance being held together by hydrogen bonds
-hydrogen bonds are transient yet enough is always held together to give
water more structure than almost any other liquid
-beads and meniscus formed by cohesion (also helps upward transport of
water in plants)
-adhesion counteracts downward pull of gravity
-water has greater surface tension than most liquids
-surface molecules are hydrogen bonded to molecules below and around
them
-surface tension can hinder life (i.e. beading in the alveoli of lungs)
-makes water “unwettable”
-surfactants used to counteract this
-water has a high specific heat which allows it to resist extreme temperature
changes
-has a high heat of vaporization that causes it to require alot of energy to
change states
-when sweating, heat energy is utilized to change states from liquid to gas,
causing a drop in temperature
-as a solid water is less dense than as a liquid and will float
-charged regions of molecules have an electrical attraction to charged ions
-water surrounds ions separating and shielding them from one another
-polar compounds are generally soluble
-charged regions of water are attracted to oppositely charged regions of
other polar molecules
-polar molecules are miscible in ot...