October 22, 2016
Aim: What is Osmosis?
COMPLETE lab report. Keep on Studying for unit test
on Thursday, topics and vocabulary is posted on class
web-page.
1. Collect data
• From last practice in new chart.
• From the rest of the groups and calculate average
• Compare your drawing and explanation for the
procedure, improve on it.
• Discuss the possible explanations for your results.
2. Osmosis definition and implications for cells.
(comparison in plant vs animal cells)
3. Summary.
October 22, 2016
2. Passive transport
Is the movement of molecules of a substance from an area where
they are in high concentration to an area where they are in low
concentration without using energy (how is that possible?)
a. Simple diffusion:
Passive transport made possible by the motion of molecules of
a solvent as they collide with the molecules around them. For
example molecules of perfume moving in a room.
(bouncing of molecules is greater in a gas than in a liquid)
Mol. of ink = Solute
Mol. of H2O = Solvent
The tendency is to
reach equilibrium.
October 22, 2016
b. Facilitated diffusion
Is the movement of molecules from an area of high
concentration to an area of low concentration
through a protein in the semipermeable membrane.
http://highered.mcgrawhill.com/sites/0072495855/student_view0/chapter2/animation__how_facilitated_diffusion_works.ht
ml
October 22, 2016
Osmosis:
http://highered.mcgrawhill.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.htm
The diffusion of water through a semipermeable membrane is called
osmosis.
Draw an example of:
Isotonic solution (show initial direction of osmosis)
Hypotonic solution (show initial direction of osmosis)
Hypertonic solution. (show initial direction of osmosis)
Plasmolysis
Case in which the balance is reached at the point in when the
cell looses cytoplasmic water. The cytoplasm shrinks
http://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter38/animation__osmosis.html
What is the difference in the result between animal cells and plant cells
when they are placed in a hypotonic solution?
What happens when they are placed in a hypertonic solution?
October 22, 2016