Answer:
B
Mutation is the ultimate source of genetic variation, but mechanisms such as sexual reproduction and genetic drift contribute to it as well Because prokaryotes are haploid, such a mutation immediately become part of the genetic makeup of the cell unlike eukaryotic diploids where a normal second copy of the gene usually protects the cell from the potentially lethal effect of such a mutation.
<span>The answer is nuclear imaging. A subject is asked to take in a radionuclide (radioactive
isotopes) and as the radioactive material passes though the body, it continually emits radiation that is detectable by an instrument such as a gamma camera. Examples of nuclear imaging
techniques are SPECT and PET.</span>
