“The Effect of NaCl, Glucose and Sucrose Solutions of Various
Concentration on Osmosis of Irish Potato”
How do the different kinds of solution of various concentration effect osmosis of Irish potato.
This investigation will use three kinds of solutions of 6 different concentrations. So the results
collect from the experiment is objective.
The deeper the concentration is, the less the mass of potato will be, so more water will osmosis
through the cell membrane to the outside.
Water is a hydrogen bond (the electrostatic attraction between polar molecules that occurs when a
hydrogen atom bound highly electronegative atom such as nitrogen, ...view middle of the document...
Water can’t pass through casparian strip directly by symplast because the cell
wall is made of Suberin which is impermeable to water. Pinocytosis is known as cell drinking, ﬂuid
endocytosis, and bulk-phase pinocytosis, is a mode of endocytosis in which small particles are
brought into the cell, forming an invagination, and then suspended within small vesicles. These
pinocytotic vesicles subsequently fuse with lysosomes to hydrolyze (break down) the particles.
This process requires a lot of energy in the form of ATP.
Water potential tells us how likely it is that water within a solution will move. Pure water have a
water potential of zero, so all solutions will have a negative water potentials. The symbol of water
potential is ψ. Water always moves from a high to a low water potential so water will always move
from pure water to a
solution. If potato cylinder
is placed in the solution
that is hypertonic, the
cells of it will lost water
and become plasmolyze.
If the potato cylinder is
placed in the isotonic
solution, the cells is
ﬂaccid. However, if the
potato is placed in the hypotonic solution,
the cells will gain water because of
osmosis and become turgid.
Solute potential is the concentration of
solute dissolved in a solution. Adding a
solute will always lower the water
potential, ψs will always be negative.
Look at the picture about the U tubes, the
P1a has more solute in the same amount
of water, so its water potential is lower
than P2a which has less solute. So the
water moves from P1a to P2a by passing
through the semi-permeable membrane
by osmosis. And this process make the U
tube like the ﬁnal state which you can see
from the picture.
In my investigation, I will use Irish potato which is white
potato. An Irish potato is an edible tuber from the Solanum
tuberous plant, which is actually native to South America, not
16 250ml beakers, 1 corer, cling ﬁlm, 16 petri dishes, a electronic balance, a ruler, 5 Irish potatoes,
100ml NaCl, glucose and sucrose of concentration of 0.1M, 0.2M, 0.3M, 0.4M, 0.5M, also the
Table 1 shows the types of variables in the investigation
The concentration of three types of solutions (0M, 0.1M, 0.2M, 0.3M, 0.4M and
The mass changes of the potato cylinders
The size of the potato cylinders (3cm)
The volume of the solutions (100ml)
The time of potato cylinders were put in the solutions (1.5h)
The temperature (room temperature)
Uncontrolled variable The mass of the potato cylinders
Using a knife to cut the potato into cubes that have a thickness of 3cm.
Using the corer to cut the potato segments into cylinders, put the potato
cylinders in the petri dishes and use the cling ﬁlm to cover the petri dishes
then the potato cylinders won’t dry out.
Measure the length of the potato cylinders, if they are longer than 3cm,