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Q3 – Week 6 – 19-20

week 6

Week of 3/9 – 3/13  – Please Refresh Every time!

*ORDER PAINTED L  and phenol shapes FOR WEEK this week or week 7 .
3/9 – Monday –  Period 7/8 
1: Homework review:  selected problems modeled
2.  Cell Membrane Lab –
Cell Membrane Lab
*You must use all solutions in your lab to test the concepts of water potential.  Your experimental design is very important. I want to see how you used controls in your data and in your analysis.
4 solutions:   
 water  CaCl2  NaCl  Sucrose
 .2 Molar  .2 Molar  .2 Molar

*you will be making illustrations of your test along with calculated water potentials for the extra cellular fluid and the cytosol of the cell.  In these illustrations arrows must be used to demonstrate the Net flow of water (osmosis).

Graphs will be made of each test to illustrate how the tested cell’s mass changes comparatively with its control.
What does your data imply for your tests?  Was dialysis tubing permeable to the solute particles?
Turgid Cell – Demo: smaller balloon has more elastic pressure on it.
3/9 – Monday – Homework
1. Please begin the write-up  of the “Water potential Lab” with the google doc that I linked today.
     This is not a group lab! You may share data but your lab write-up and especially your analysis is       your own.  
Cell Membrane lab –  Informal Lab Requirements:
1.  Title
2.  Hypothesis (if the independent ..the dependent variable ….)
2a.  Discussion of controls – What controls are you using?  Why?  What environmental factors are you keeping       
3.  Data
    a) Diagrams of each test – Include water potential for the Cells and Extracellular fluid and the calculations               for each.  The diagrams must have arrows to show the net osmosis of water and label the type of     
            solution that the extracellular fluid is  respect to the cell.
    b) Data tables 
    c)  Graphs of each test (with the control).  Make a line of best fit (regression line) and include the equation 
          (y = mx + b). We are after the slope of the graph (change of mass / change of time).   The slope of the cell    
          tested will be compared to the slope of the control cell. You can use logger pro or excel to determine your   
          line of best fit (regression) to get your slope.
        We will use the premise that the greater the slope the greater the difference in water potential between the              cell and the extracellular fluid.
     d) Conclusion – THIS MUST BE YOUR OWN ANALYSIS!!! You can share data but this part must be             your own work.  Tie in your hypothesis and analyze your data. Make a leap.  Think about how             organisms osmoregulate and what physical parts of the cell are responsible.
          Errors Analysis –
How to determine the best fit line and Slope in Excel.
End of Monday…

3/10 – Tuesday – period 7 – Academic Study Hall
                                period 8 – 
1: work of Homework forms
2: data gathering and graph making (instructions in homework last night) for cell membrane lab.
3.  Limitations in Lab based on data.
diffusion/passive transport = spontaneous
Active transport – (require ATP) = nonspontaneous
Reverse osmosis = non spontaneous.
1:  Cell Membrane lab requirements
2:  Osmoregulation in Paramecium/protists/ reverse osmosis – non
3. Stomata/guard cell – 
4:  Dialysis
5: Pores in the Cellulose tubing
– up to slide 28 in the Cell membrane presentation

Water Potential Lab – Cell Model


Cellulose vs Starch


Cell Membrane

Pete the Paramecium:


Cell Membrane Whiteboards:  And the winner is!!!!!!!


3/10 – Tuesday Homework- 
1:  Please use your book to begin your initial learning of Cell – Cell communications that result  from receptors on the cell membrane, completing the form below:
2: Cell Membrane Lab – write-up – Informal due this Thursday 
3. Water Potential Test – This week ! (This Friday!)
Here are the keys to the 2 forms this week.
Water Potential Form 1 – Key.pdf
View Download
Water potential Form 2 page complete key p.pdf
View Download
Cell communication form:  Form is now open

Cell communication Form 1920

End of Tuesday..

3/11 – Wednesday – Period 7/8 – 
60 minute segment on gene therapy
1.  Diffusion Lab – Surface area to volume ratio
2. Diffusion races – design a cell – Winner has the greatest mass to second ratio. 
Why do we need cells? Why are they so small small?  Why are prokaryotes smaller than eukaryotes?
Diffusion Lab – Grodski new.pdf
View Download
  1. No donut-like holes through the agar cell — cell membranes cannot sustain that shape.
  2. No poking, prodding, touching beaker containing agar cell in vinegar.
  3. Teacher determines when 100% diffusion takes place.
  4. Students mass agar at conclusion of race…cell must not break when handled. Disqualification if cell breaks upon massing (although you can be a bit lenient here).
  5. No slivers or shaved cells.  Cells must be at least 1 cm in width.
  6. Winner = highest ratio of mass divided by time.
3/11 Wednesday HW: 
1: Cell Communication Form 2 –
2: Diffusion Lab Due – Thursday 3/12 –
    You have all you need to complete the lab, using the video for each class posted above.
    This is a packet lab we will complete tomorrow.
3: Cell Membrane lab – due Friday 3/13 .
NOW what can we take from the Diffusion Lab that will help us in out error discussion?  Hmm? Did you make all of your model cells the same size and shape?  How would this affect osmosis (which is passive diffusion of water)?
Cell membrane Lab – (Rate of Osmosis) requirements:  On separate paper of your choosing.
a) You will need a sketch or diagram of each different cell (labeling the intracellular and extra cellular chemical 
      and their respective concentrations.
b) Calculate the water potential for the cell and extracellular fluid and label your diagram with those values.
      Show all calculations
c) Label the intracellular and extra cellular as either Isotonic, Hypotonic, or Hypertonic.
d) Draw an arrow in your sketch that illustrates the net movement of water (from high potential to lower  
    potential).  The ARROW and its size is really your hypothesis.  The size of your arrow is how  
    you rank your test cells in terms of the greatest rate of diffusion. Remember this is a rate  
   (speed or time) lab.
e) Place your graph with its slope alongside the sketch.
g) Write a conclusion that analyzes your results.  Some cells will not lose or gain mass as you suspect because  
     dialysis tubing is really cellulose which compromises the cell wall of plants and is not semi-permeable as you       
     expected in your calculations.   Its pores allow water to diffuse AS WELL as Ca+2, Na+1, Cl- . Sucrose is too large      to pass through.  If you remember that dialysis was used to diffuse out urea, water, and ions out of the blood   
     when the kidneys are not functioning properly, this makes sense.

Cell Communication 1920 Form 2


Diffusion Time lapse:

YouTube Video

End Wednesday..

3/12 – Thursday – Period 7 –  Academic Study Hall – 
                                   Period 8
1.  Cell design part of the lab 
2. Lab questions  –
      – completed math to determine the winner
      – completed questions in class
      – Handed in the packet lab into the purple crate of fun.
3/12  Thursday Homework: – Test Friday – Water Potential problems only!
Water potential worksheet Key p.pdf
View Download
Water Potential worksheet.pdf
View Download
Water Potential 2 worksheet fixed.pdf
View Download
Water Potential 2 worksheet KEY final.pdf
View Download
Water Potential worksheet review lecture:


Water potential review lecture:


This Year’s Cell Diffusion races:
Congrats to the winners!
Honorable Second Place did not win group:

3/13 – Friday – Period 7/8-  
– Water Potential Test – period 7
– Energy Dynamics lab – period 8
Painted Lady Butterfly Lab Begins- 
  a) growth chambers measured


Write name of group on the top lid with sharpie.
1. Mass out Cup, Lid, and tissue paper.  Write C = ____g on cup.
2. Add about 12 g food  by taring the cup. Write F = _____g on cup.
3. Add  2 – 4 Larva per Cup. Tare out cup with food to measure just the mass of the     larva.  Write L = _____g on cup.
4. Place the entire system, cup, tissue, lid, larva on scale and find entire mass.
   write total = ________ g on cup.
3/13 – Friday – Weekend Homework: 
HW: We are digging into Chapter 11!
Chapter 45, Chapter 11
1.  Please use the Google Doc that I have linked with you and complete the following:
I would like a mini-report on the “Fight or Flight” response that must include the following:
A) Epinephrine – 
B) Signal Transduction pathway – of Epinephrine – (diagram of pathway)
    1) specifics about how the chemical signal produces a response
    2) What type of receptor was used (pages 211 – 213)
    3) How does does cAMP fit into the other parts of our course?
C) Evolution
You must use the following the terms:
Cyclic AMP 
Adenyl cyclase
first messenger
second messenger
Phosphorylation cascade
Adrenal Gland
A Tortoise


If you use other sources beside the text then you have to show sources.
THis should not exceed 2 pages.
Have a weekend..