Water Properties
(from a Biological perspective)
Importance of Water
Fills and surrounds cells
 2/3 of human body
 Required for chemical rxns
 Maintains homeostasis
 Essential for life!

A Water Molecule
1
oxygen
atom and 2
hydrogen
atoms joined
by covalent
bonds
Polarity of Water
Polar - electrons
are not shared
equally
 Oxygen end of
water molecule
attracts electrons
more, giving it a
negative charge
 H2O molecules
“stick” together
forming weak H
bonds

Cohesion of Water
Water is “sticky”
 When water is attracted to
other water molecules,
cohesion occurs
 allows H2O to form drops,
thin films, and have surface
tension

Adhesion of Water
 When
water is attracted
to non-water molecules,
adhesion occurs
 Adhesion enables water
to travel from roots
through stems to leaves
of a plant
Water has a High
Specific Heat
 Water
resists changes
in temperature
 H2O is critical to
homeostasis
– Ex. Near constant
body temperature
maintained
Solubility of Water
 Many
substances are soluble
(easily dissolve) in water
 Water is called a universal solvent
 Essential for homeostasis
– Ex. Transport glucose into cells
– Ex. Move substances within the cell
– Ex. Carry wastes out of cell
 H2O
is essential for chemical
reactions / metabolism and the
chemistry of life!