Worksheet Flashcards
Of the various macromolecules sensitive to radiation damage, ___ are considered the most sensitive.
DNA
The biologically reactive molecular by-products formed during radiolysis of water are thought to be ___?
H* and OH*
*=free radical
Usually, radiation interacts with DNA:
A. Directly
B. Indirectly
Indirectly
Free radical ions are associated with biological injury induced by which type of radiation?
Diagnostic x-ray
Chromosome aberrations can A. Lead to cell death B. Occur in a genetic cell C. Result in abnormal metabolic activity D. All of the above
All of the above
Which of the following is true about the target theory? A. A key sensitive molecule exists B. Radiation interaction is nonspecific C. Radiation interaction is random D. All
All of the above
When water is irradiated, by products of the initial encounter are:
HOH+ and e-
Which of the following is an example of anabolism? A. Radiolysis of water B. Main-chain scission C. Protein Synthesis D. Transfer RNA
C. Protein synthesis
An atom or molecule having an unpaired electron in its outer shell is called?
Free radical
A comparison of G1 and G2 phases indicates that:
A. They both require the same time
B. There is twice the DNA in G1 as in G2
C. There is twice the DNA in G2 as in G1
C. Twice the DNA in G2 as in G1
DNA synthesis occurs during?
The S phase
What phase can you see radiation damage?
Metaphase
Which of the following would be most sensitive to irradiation? A. Erythrocytes B. Lymphocytes C. Leukocytes D. Platelets
B. Lymphocytes
Which cells are the most radiosensitive?
Erythroblasts
The photoelectric effect is the interaction between x-ray photons and matter that is largely responsible for patient dose. The photoelectric effect is most likely to occur under the following conditions?
- With absorbers of high atomic number
- With low energy incident photons
- With the use of positive contrast agents
All 3
What are electrically charged particles called?
Ions
Where are ions located? What gets ionized?
In molecules.
Atoms get ionized
Why are ionization events significant?
Ion and free e- have potential to cause damage
What can ions do to living tissue?
Create unstable atoms, cause + and - charged ions, create free radicals, create new biologic molecules, alter normal function of cells
List the properties of x-radiation
Invisible Varying degrees of penetration Not influenced by magnetic or electrical fields Have no mass or charge Travel at speed of light in straight line Cause certain materials to fluoresce Cannot focus them with a lens Will darken photographic film Heterogeneous beam
What are the goals of radiation protection programs?
Protect from short and long term effects
Where can radiation effects occur in the body?
Organs
Whole body
Future generations
Define radiation protection
Measures employed by radiation workers to protect themselves, patients, co-workers, public, from unnecessary exposure to ionizing radiation
What is “necessary” radiation?
Limiting scatter and secondary radiation
