Chapter 4 Radiation Biology Questions
and Answers| Latest Update
A single intraoral radiograph (D-speed film, 70kVp, long PID) results in a mean surface exposure
of:
a. 50 mR
b. 250 mR
c. 500 mR
d. 1 R
e. 5 R B
What is the dose at which leukemia induction is most likely to occur?
a. 500 mrads (0.005 Gy)
b. 1000 mrads (0.01 Gy)
c. 2000 mrads (0.02 Gy)
d. 5000 mrads (0.05 Gy)
e. none of the above D
Which of the following statements is incorrect?
a. x-radiation is not harmful to living tissues
b. dental radiographs benefit the patient
c. in dental radiography, the benefit of disease detection outweighs the risk of damage from
radiation
d. radiography should be prescribed only when the benefit outweighs the risk
e. biologic damage results from x-ray exposure A
What two specific mechanisms of radiation injury are possible when chemical changes occur
that result in biologic damage? Ionization & Free radical formation
, what type of theory is it when cell damage results when ionizing radiation directly hits critical
area or targets, within the cell. They occur infrequently direct theory
What type of theory is it when X-ray photons are absorbed within cell causing toxins thus
damaging the cell. Free radicals combine to form toxins causing cellular dysfunction and
biological injury indirect theory
What are the three periods in the sequence of radiation injury? latent, period of injury,
and recovery
What is the most radiosensitive cell? small lymphocyte
what is the most radioresistant cell? muscle tissue
The amount of exposure varies, depending on the following: film speed, collimation,
technique, and exposure factors
The latent period in radiation biology is the time between Exposure to x-radiation and
clinical symptoms
A free radical: ALL, is an uncharged molecule, has a unpaired electron in the outer shell ,
is highly reactive and unstable, combines with molecules to form toxins
What type of radiation injury is it when X-ray photons hit critical targets within a cell
Direct radiation
what type of radiation injury occurs when X-ray photons are absorbed and form toxins
Indirect radiation
and Answers| Latest Update
A single intraoral radiograph (D-speed film, 70kVp, long PID) results in a mean surface exposure
of:
a. 50 mR
b. 250 mR
c. 500 mR
d. 1 R
e. 5 R B
What is the dose at which leukemia induction is most likely to occur?
a. 500 mrads (0.005 Gy)
b. 1000 mrads (0.01 Gy)
c. 2000 mrads (0.02 Gy)
d. 5000 mrads (0.05 Gy)
e. none of the above D
Which of the following statements is incorrect?
a. x-radiation is not harmful to living tissues
b. dental radiographs benefit the patient
c. in dental radiography, the benefit of disease detection outweighs the risk of damage from
radiation
d. radiography should be prescribed only when the benefit outweighs the risk
e. biologic damage results from x-ray exposure A
What two specific mechanisms of radiation injury are possible when chemical changes occur
that result in biologic damage? Ionization & Free radical formation
, what type of theory is it when cell damage results when ionizing radiation directly hits critical
area or targets, within the cell. They occur infrequently direct theory
What type of theory is it when X-ray photons are absorbed within cell causing toxins thus
damaging the cell. Free radicals combine to form toxins causing cellular dysfunction and
biological injury indirect theory
What are the three periods in the sequence of radiation injury? latent, period of injury,
and recovery
What is the most radiosensitive cell? small lymphocyte
what is the most radioresistant cell? muscle tissue
The amount of exposure varies, depending on the following: film speed, collimation,
technique, and exposure factors
The latent period in radiation biology is the time between Exposure to x-radiation and
clinical symptoms
A free radical: ALL, is an uncharged molecule, has a unpaired electron in the outer shell ,
is highly reactive and unstable, combines with molecules to form toxins
What type of radiation injury is it when X-ray photons hit critical targets within a cell
Direct radiation
what type of radiation injury occurs when X-ray photons are absorbed and form toxins
Indirect radiation
