? Happy Tuesday ? Bellwork: Quickwrite

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? Happy Tuesday ?Bellwork Quickwrite In 42
words, summarize your HW using the words
concentration, diffusion, osmosis, equilibrium,
isotonic, hypertonic, and hypotonic.On Page 17
of your I.A.N. Title Egg Lab and draw the
following data table
Original Mass Final Mass Difference in Mass Appearance of Egg
VINEGAR XXXXXXXXX XXXXXXXXX
SYRUP
WATER
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On Page 17 of your I.A.N. Title Egg Lab and
draw the following data table
Original Mass Final Mass Difference in Mass Appearance of Egg
VINEGAR XXXXXXXXX XXXXXXXXX
SYRUP
WATER
The shell that surrounded your egg was dissolved
by soaking the egg in vinegar for 24 hours. The
vinegar dissolved the hard calcium carbonate
shell exposing the semi-permeable membrane that
surrounds the egg. This membrane is very similar
to the plasma membrane that surrounds all of our
cells. The purpose of this lab is to simulate
osmosis across a plasma membrane. Students will
receive one egg per lab table.
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Day 1 Procedure

1. Using your hands, carefully remove your egg from
   the vinegar and use a paper towel to pat it dry.
2. On your data table, record the firmness and
   overall appearance of your egg in the VINEGAR
   row.
3. Mass (weigh) your egg on a triple beam balance
   and record your results on your data table.
   Enter the weight under the Final Mass for
   VINEGAR and the Original Mass for SYRUP.
4. Using a piece of glassware tape and a marker,
   label the beaker with your period and table
   letter. Cover the egg with syrup until it begins
   to float.
5. Allow your egg to sit for 24 hours.

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Diffusion Notes Why does food coloring spread
out in water?
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Every living thing lives in a liquid environment
that it needs to survive.
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One of the most important functions of the cell
membrane is to regulate the movement of dissolved
molecules from the liquid on one side of the
membrane to the liquid on the other side.
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The concentration is the amount of a substance
dissolved into water.
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Kool-Aid
Beaker 1
Beaker 2
Beaker 3
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In a solution, particles are constantly
moving.They collide with one another and tend
to spread out randomly.
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Particles move from an area of high concentration
to an area of low concentration.This process is
known as diffusion.
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A concentration gradient is a difference between
two concentrations.Diffusion is the movement of
particles down the concentration gradient.
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When the concentration of a solute is the same
throughout a system, the system has reached
equilibrium.When equilibrium is reached,
particles do continue to move across the membrane.
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Substances that diffuse across a membrane do not
require the cell to use energy.
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If a substance is able to diffuse across a
membrane, the membrane is said to be permeable to
it.If a substance cannot diffuse across a
membrane, the membrane is said to be impermeable
to it.
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Selectively permeable means that some substances
can pass across while others cannot.Biological
membranes are selectively permeable.
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Diffusion of water through a selectively
permeable membrane is called osmosis.
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When two solutions have the same concentration of
solute they are said to be isotonic.Isotonic
means same strength.
Draw This
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A solution that has a higher concentration of
solute is said to be hypertonic.Hypertonic
means above strength.
Draw This
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A solution that has a lower concentration of
solute is said to be hypotonic.Hypotonic means
below strength.
Draw This