Week 8

Question 1

Does the absorption of the Heidbrinkions depend on the atomic charge of the absorber, Z

Answer 1

Yes

Question 2

Which metastable radionuclides are preferable to other radionuclides for diagnostic imaging in nuclear medicine?

Answer 2

Metastable radionuclides that have already undergone an electron-emitting transition.

Question 3

There is really only one way a sealed alpha source can hurt you. What is it?

Answer 3

by ingestion

Question 4

In the PET technique, detectors record the emission of_____________________ from active substrates to form a tomographic image of the cross-sectional distribution of tissue concentration.

Answer 4

gamma rays

Question 5

Lower energy particles can act on an atomic electron for a greater length of time, thus increasing the probability of driving an electron out and causing ionization. Thus___________ ______________ are more damaging than __________________ ____________________.

Answer 5

alpha particles; gamma rays

Question 6

On the graph, the mass absorption coefficient is given by

Answer 6

the negative of the slope of the line

Question 7

How do radioiodine experiments diagnose hyperthyroidism/ hypothyroidism?

Answer 7

A hyperactive thyroid may absorb up to 80% of the tagged iodine; a hypoactive gland may absorb as little as 15% of 131I.