lab 9: radioisotopes and fluorophores in biochem rxns

1. Radioisotopes were originally used in biochemistry to:

B. Elucidate metabolic pathways

2. Modern biochemistry uses radioisotopes for:

C. A diverse range of applications

3. One advantage of radioisotope techniques is:

B. They can detect minute quantities

4. Second major advantage of radioisotopes:

C. They differentiate chemically indistinguishable substances

5. Radioactivity results from:

B. Spontaneous nuclear disintegration

6. Tritium is radioactive because:

B. It has an unstable neutron-to-proton ratio

7. The file lists three types of radiation emitted in decay:

B. α, β, and γ

8. Most biochemistry radioisotopes are:

B. β-emitters

9. Standard unit of radioactivity is:

C. Curie (Ci)

10. One curie equals:

B. 3.7 × 10¹⁰ disintegrations/sec

11. Microcurie equals:

B. 2.2×10⁶ dpm

12. Liquid scintillation samples contain radioactive material plus:

B. Solvent and fluorescent molecule(s)

13. Scintillation flashes are detected by:

C. Photomultiplier tube (PMT)

14. Gamma rays require:

B. Denser materials for absorption

15. Major concern when working with radioisotopes:

C. Safety precautions

16. Labs handling radioisotopes require:

B. Specially equipped facilities or designated areas

17. Fluorophores emit light when:

B. Excited and returning excess energy

18. Fluorophores are replacing radioisotopes because:

C. They avoid health hazards

19. Fluorescent compounds are detected using:

B. Fluorimeter

20. A radioactive compound differs from fluorescent in that:

B. Radioisotopes spontaneously emit radiation

21. Example applications of radioisotopes include:

B. DNA sequencing and metabolic tracing

22. Liquid scintillation detection requires:

B. Organic scintillation cocktail

23. β-particles interact with scintillation system to produce:

C. Light flashes

24. Fluorescent molecules emit at:

B. Longer wavelength than excitation

25. One reason for favoring fluorescence over radioactivity is:

C. Reduced hazard

26. Fluorophores used commonly include:

B. GFP and fluorescein

27. Radiation detection equipment must count:

B. Light pulses from scintillation

28. Units mCi and μCi are commonly used because:

A. Ci is too large

29. Fluorimetry eliminates:

C. Radiation hazard

30. Core safety requirement before radioisotope use:

B. Special equipment and guidelines