Review Questions

1. What is the most commonly used imaging technique to visualize changes in living systems in basic research laboratories?
   1. Magnetic Resonance Imaging (MRI)
   2. Fluorescence/optical imaging
   3. Positron Emission Tomography (PET)
   4. Electron microscopy


2. Why can’t glycans be labeled with genetically-encoded reporters?


3. A “bioorthogonal” reaction is a reaction that…
   1. doesn’t interact with biology
   2. is mutually and selectively reactive
   3. is not harmful to the biological system
   4. All of the above


4. What monosaccharide is used as the starting point for sialic acid biosynthesis?
   1. N-acetylmannosamine
   2. Xylose
   3. Fucose
   4. N-acetylgalactosamine


5. What are the names of two reactions used as bioorthogonal reactions?


6. Why do bioorthogonal reactions need to be very fast reactions for imaging in live animals?


7. Why is a strained alkyne so much more reactive with an azide than a linear alkyne?


8. Why are zebrafish a good model organism for optical imaging?