Transcript _30 Diffusion State Lab - Bronx Envision Academy

#30 How did
we observe
diffusion in
the State
Lab?
#30 Warm UP
How did we use
indicators in the
Diffusion Lab?
Find your
Diffusion
Lab
#30 How did
we observe
diffusion in
the State
Lab?
Review of the Cell Membrane
• The Cell Membrane is SemiPermeable or Selectively
Permeable
• Small molecules (like glucose)
are able to pass through the
membrane while large molecules
(like starch) cannot pass through
#30 How did
we observe
diffusion in
the State
Lab?
What we used for the lab
• Dialysis Tubing – used to make a
“cell” that will allow small particles to
pass through and not large particles
• Glucose Solution – a simple sugar
made of one small molecule of sugar
• Starch Solution – a complex
carbohydrate made of hundreds of
simple sugars bonded together
#30 How did
we observe
diffusion in
the State
Lab?
Indicators
• Starch Indicator Solution – (Iodine), a
really small molecule (It’s only 2 atoms big)
• Glucose Indicator Solution – Benedict’s
solution
#30 How did
we observe
diffusion in
the State
Lab?
Initial Cell
“Cell” with
glucose
and starch
Water and
starch
indicator
solution
#30 How did
we observe
diffusion in
the State
Lab?
The Final Cell
The water
stayed amber
The cell turned
blue-black
Water from outside
the cell tested positive
for glucose
#30 How did
we observe
diffusion in
the State
Lab?
What Happened??
• Glucose was small enough to pass
through the membrane so it ended up in
the water outside the cell
• Starch was too big to pass through the
membrane so it didn’t get out of the cell
• Iodine (starch indicator solution) was
small enough to pass through the
membrane so it ended up in the cell turning
the cell blue-black
#30 How did
we observe
diffusion in
the State
Lab?
RED ONION IN FRESH WATER
#30 How did
we observe
diffusion in
the State
Lab?
CELL WALL
CELL MEMBRANE
CYTOPLASM
#30 How did
we observe
diffusion in
the State
Lab?
RED ONION IN SALT WATER
#30 How did
we observe
diffusion in
the State
CELL
Lab? WALL
CELL MEMBRANE
CYTOPLASM
#30 How did
we observe
diffusion in
the State
Lab?
Activity – Analysis
Questions
• Your table will be assigned one question from the
analysis section on pages 8 and 9
• Work on the question with your table for 5 minutes
and put your answer on your easel.
• Be ready to share and explain to your classmates
** If you finish early, check that ALL other sections
of the lab are complete
#30 How did
we observe
diffusion in
the State
Lab?
REGENTS
PRACTICE
Reflection
Answer on looseleaf and attach to lab
1. How did we observe diffusion and osmosis
in this lab activity? Did this help with your
understanding of these concepts? Explain.
2. Why was lab safety important during this
activity?
3. What was your favorite part of this lab?
What was most challenging?