HAPPY THURSDAY
• First things First - Goggles and Aprons!!!
• Bellwork: Draw the picture below and label the essential parts
of the cell membrane and their function.
2.
1.
3.
Standard
PG 34
B.4B – Investigate and explain cellular
processes, including homeostasis, energy
conversions, transport of molecules, and
synthesis of new molecules
Essential Question
How do molecules move across the cell
membrane?
Day 2 Procedure…
1. Using your hands, carefully remove your egg from the syrup and use the
water bath to CAREFULLY rinse off any excess syrup. Use a paper towel to
pat it dry.
2. On your Cornell notes, record your observations (firmness and overall
appearance) of your egg in the SYRUP column. Draw a diagram.
3. Mass (weigh) your egg on a scale and record your results on your data
table. Enter the weight under the “Final Mass” for SYRUP and the “Original
Mass” for WATER. Subtract the “Final Mass” from the “Original Mass” in
the SYRUP row. Place this number in the “Difference in Mass” column in
the SYRUP row.
4. Clean the cup, place your egg in the cup, and cover the egg (CAREFULLY –
low water pressure) with distilled water.
5. Allow your egg to sit for 24 hours.
6. Fill in Cornell Notes “Prediction” (self) and “Hypothesis” (lab group) for the
“Water” Column.
Egg Lab
Hypothesis:
L2 –
Observation:
L3 –
Diagram:
Summary -
Egg in Water
Prediction:
Prediction:
Hypothesis:
Hypothesis:
Observation:
Diagram:
Observation:
Diagram:
TODAY
Prediction:
Egg in Syrup
TOMORROW
L1 –
Egg in Vinegar
TODAY – NOW
Question Column
How do molecules move across the cell membrane?
TODAY – DONE
Essential Question:
Page 33
Diffusion Notes
Why does food coloring spread out in water?
Every living thing lives in a liquid environment
that it needs to survive.
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.
The concentration is
the amount of a
substance dissolved
into water.
Kool-Aid
Beaker 1
Beaker 2
Beaker 3
In a solution,
particles are
constantly
moving.
They collide
with one
another and
tend to spread
out randomly.
Particles move from an area of high
concentration to an area of low
concentration.
This process is known as diffusion.
A concentration gradient is a difference
between two concentrations.
Diffusion is the movement of particles
down the concentration gradient.
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.
Substances that diffuse across a membrane
do not require the cell to use energy.
Diffusion
High
No Energy
Low
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.
Selectively permeable means that some substances
can pass across while others cannot.
Biological membranes are selectively permeable.
Start foldable if time…….
PG 35
Lipid Heads– Green
Lipid Tails – Blue
Proteins- Purple