[Campbell Biology P.81] In a PET scan, radioactive isotopes are used to label glucose. What... | Practice Question

In a PET scan, radioactive isotopes are used to label glucose. What is the primary reason for using labeled glucose to detect cancerous tissue, according to the provided text?

  • A: Cancerous tissue produces more radioactive isotopes, which can be detected by PET.
  • B: Labeled glucose indicates areas of high metabolic activity, which is a hallmark of cancerous tissue.
  • C: Radioactively labeled glucose directly binds to cancer cells, allowing them to be visualized.
  • D: PET scans detect the physical mass of tumors, which are often composed of glucose.

Explanation

According to the 'Figure 2.5 A PET scan...' section, 'The bright yellow spot marks an area with an elevated level of radioactively labeled glucose, which in turn indicates high metabolic activity, a hallmark of cancerous tissue.' This directly explains why labeled glucose is used: to identify areas with high metabolic activity, characteristic of cancer cells.