What are radioisotopes used to find and keep track of molecules of an organism?

Answer 1

A radioisotopic tracer is used in Biology to help trace the chemical reactions in living organisms. In this technique, one or more of the atoms of the molecule of interest is substituted by an atom of the same chemical element, but of a different isotope. Because the atom has the same number of protons, it will behave in almost exactly the same way chemically as other atoms in the compound, and with few exceptions will not interfere with the reaction under investigation. The difference in the number of neutrons, however, means that it can be detected separately from the other atoms of the same element. Small amounts of radioactive atoms can be readily detected.

For example the radioactive isotope of carbon, carbon-14, was used by Melvin Calvin and his colleagues to trace the path of carbon in the light independent reactions of photosynthesis. In another classic experiment Hershey and Chase used radioactive isotopes of phosphorous and sulphur to show the DNA, not protein, was the genetic material in viruses. They can also be used to trace the path of food through a food chain. See http://www.allinterview.com/showanswers/1668.html http://www.accessexcellence.org/RC/VL/GG/hershey.html http://courses.bio.psu.edu/fall2005/biol110/tutorials/tutorial29.htm

Answer 2

In a previous job, we used to manufacture C11 in a linear accelerator, and from this make CO2 and this was fed to the plants. (half life of 20.3 min!)

The emission from the disintegration of this into Boron was measured with a KI (?) scintillation counter with integrated photomultiplier.

For Nitrogen we used the same accelerator to make N13, (half life 10 min!) and this was used as either ammonia, or as nitrate. Had to be a bit snappy with the chemistry, as the accelerator was several minutes from the plant cabinets.

No doubt many other isotopes are available.

[I seem to recall that the C11 was made from Lithium, but that was all more than twenty years ago. I'm sure that the plants were not happy to discover that the sugar they had just made now collapsed into a mess containing Boron.]

Answer 3

To use a radioactive isotope as a tracer, you simply introduce a compound containing it into the system you're looking at at the chosen starting point, then look for its radioactivity at the test points.

Answer 4

radioactive Florine is attached to glucose molecule , so where is the excessively highly glucose utilization and show up in...........

if u want more sand me mail

Answer 5

the right anwer