BIO 120 Lab - PhysioEx Help Needed!

Biology 120
Lab Report 1

Name:  _____________________________ _________

Use complete sentences to type your answers to the following questions, or type your answers into the table.  You may type them in this word document, then print it out and bring it to lab.  Remember, no handwriting is permitted.  Do NOT copy information from a textbook, journals, fellow students, or the Internet!  Paraphrased material must include correct citations.

1.  A. Explain the differences between passive and active transport across cell membranes.

     B.  For the following, indicate whether the method is passive or active:
   
   Active Transport     _______      Filtration         _______

   Diffusion      _______      Facilitated Diffusion      _______

   Endocytosis      _______      Secondary Active Transport   _______

   Osmosis      _______      Exocytosis         _______

      C.  Explain why substances need to cross the cell membrane.


2.  A. Explain the term “concentration gradient”.  Make sure to discuss the difference between a
          solution's concentration and a concentration gradient.


     B. An artificial cell contains 0.03 M sucrose and 0.02 M glucose.  It is placed into a solution
          containing 0.01 M concentrations each of sucrose, glucose, and fructose. The ‘cell’
          membrane is permeable to glucose and fructose, but not sucrose.

   1.  For which solutes do concentration gradients exist?

   2.  Which solute(s) will exhibit net diffusion into the cell?

   3.  Which solute(s) will exhibit net diffusion out of the cell?
   

3.  List and explain at least three things that influence whether a molecule will be able to pass
     through a biological membrane.


4.  A.  Define osmosis.

     B.  What is meant by osmolality? (No. The term is not osmolarity.) 

5.  With reference to solutions in the human body, differentiate among hypotonic, hypertonic, and
     isotonic.  Remember: These terms are always used to compare two solutions.



6. Ringer’s solution is often given to patients through an IV.  With reference to the osmolality
    of human red blood cells, how would you describe Ringer’s solution? (Hint:  See question 5.)



7. Define the terms ‘crenate’ and ‘lyse’ with respect to human cells.



8.  A.  Indicate the method(s) of transport across the cell membrane for each of the following.
     B.  Indicate whether the method(s) is(are) active or passive by writing "active" or "passive" in
           the chart.  There may be more than one answer for each.

                  Method(s)         Passive/Active

   A.  Glucose

   B.  Amino acids

   C.  O2

   D.  CO2

   E.  H2O

   F.  Urea

   G.  H+, Na+, K+, Ca++

   H.  Pancreatic digestive enzymes

9.  Explain how the number of glucose carrier proteins in the membrane in PhysioEx Exercise 1,
     activity 2 affected the rate of glucose transport.  Why does this occur?




10. A. Thoroughly explain the cause of the osmotic pressure generated in activity 3. 



    B.  Under what circumstances was no osmotic pressure generated?  Why?

1.  A. Explain the differences between passive and active transport across cell membranes.

     B.  For the following, indicate whether the method is passive or active:

2.  A. Explain the term “concentration gradient”.  Make sure to discuss the difference between a
          solution's concentration and a concentration gradient.


     B. An artificial cell contains 0.03 M sucrose and 0.02 M glucose.  It is placed into a solution
          containing 0.01 M concentrations each of sucrose, glucose, and fructose. The ‘cell’
          membrane is permeable to glucose and fructose, but not sucrose.

   1.  For which solutes do concentration gradients exist?

   2.  Which solute(s) will exhibit net diffusion into the cell?

   3.  Which solute(s) will exhibit net diffusion out of the cell?

could you answer number 8?