Transcript Document

•
Isotonic solutions:
• if the osmotic
concentrations of
both solutions are
equal than no net
movement of
water occurs
• Examples include
most interstitial fluid
and most intravenous
solutions
• Hypertonic solution: the solution has
more dissolved particles, salts, sugar,
etc., than is in the cells, so cells will
shrivel up or shrink as water moves
out of the cell
• If red blood cells are exposed to a
hypertonic solution- a solution that
contains more solutes, or dissolved
substances, than there are inside cellsthe cells will shrink, or crenate as water
moves outside the cell (this is because
water is in higher concentration inside the
cell than outside, so it follows its
concentration gradient and leaves the cell)
http://highered.mcgrawhill.com/sites/0072495855/student_view0/chapter21/animation__hemolysis_and_crenation.html
• Crenation is the
contraction of a
cell after exposure
to a hypertonic
solution, due to the
loss of water
through osmosis
Crenation
Would patients ever be given
hypertonic solutions?
• Yes, if they have
edema (swelling of
•
the feet and hands
due to fluid retention)
Such solutions draw
water out of the
tissue spaces into the
bloodstream so that
the kidneys can
eliminate excess fluid
Hypotonic solution:
• Solution has less
dissolved particles,
salts, sugar, etc., than
is in the cell; cells
swell and can burst
as water enters the
cells
Hypotonic solution:
• Distilled water is an
•
example of this type of
solution (there are no
solutes). Water will enter
cells until they finally
burst, or lyse.
Given intravenously to
rehydrate tissues of
extremely dehydrated
patients