Sample Exam

1. (16 points)Answer two (2) and only two of the following 3 questions.
   1. Describe the nature and extent of the associations of (1) band 3 protein   and (2) ankyrin with the membrane of the mammalian erythrocyte RBC.
   
   
   2. Describe the general sequence of steps one would follow in order to perform cytochemical localization of a particular enzyme at the level of TEM.   You may describe the process for a specific enzyme we discussed, or for a hypothetical enzyme.   Be complete.
   
   
   3. “Mitoplasts” are isolated mitochondria from which the outer membrane has been removed.   They can perform oxidative phosphorylation if supplied with the appropriate substrates.   If the mitoplast membrane is broken, they lose their ability to make ATP.   Explain this observation.

2. (24 points)   Answer two (2) and only two of the following 3 questions.


1. Relate the discrete steps involved in the action of the mammalian Na+K-ATPase to the coupling between movement of ions up their electrochemical potentials and the release of energy via hydrolysis of ATP.


2. Describe briefly the energetic principle that allows the Na⁺ -H⁺ antiport of mammalian cells to extrude H⁺ from cells against an electrochemical gradient.


3. Describe and account for the effects that peripheral membrane proteins might have on the lateral mobility of integral membrane proteins.   Be thorough.

3. (24 points)   Answer four (4) and only 4 of the following 6 questions (a-f).


1. Briefly compare the general organization of “columnar” epithelial cells to that of   “cuboidal” epithelial cells.


2. What is the purpose of the dehydration steps used in preparing a tissue specimen for transmission electron microscopy?   Why is this important?


3. Briefly compare and contrast “active transport” and “facilitated diffusion”.


4. What is the role of glutaraldehyde in preparing tissue for transmission electron microscopy?   In general terms, how does it work?


5. Explain very briefly the general principle by which an SEM image is formed.


6. What can freeze-fracture tell us about membrane proteins?   Be brief.

4. (36 points)   Identify or illustrate nine (9) and only nine of the following.   (Omit 4.)


1. example of an ABC transporter


2. “electron lucent cell component”


3. glycophorin


4. ligand-gated channel


5. material identified with PAS reaction


6. NADH dehydrogenase complex


7. P face


8. photosynthetic phosphorylation


9. primary active transport system


10. feature identified by ruthenium red staining of the surface of eukaryotic cells


11. squamous


12. thylakoid


13. uniport