E2
What are Stochastic Effects?
non-threshold, randomly occurring biologic somatic changes.
Why are the results of Chromosome Aberrations significant?
can lead to abnormal cell activity or cell death
In regard to DNA chains, what bonds with one another?
1. held together by hydrogen bonds, form specific nitrogenous bases.
2. adenine and thymine pair with 2 hydrogen bonds
3. cytostine and guanine pair with 3 hydrogen bonds.
What is LET?
1.Linear energy transfer.
2. measurement of energy transferred into matter from ionizing radiation.
What is Epilation?
hair loss, caused by exposure to radiation since hair follicles are growing tissue.
What are some examples of Stochastic effects?
hereditary effects, carcinogenesis (cancer), radiation risks.
What is: Photons comes in and breaks a piece of chromosome off but it reattaches?
resitution
Which type of cell group is MOST radiosensitive?
lymphocytes.
what forms as a result of radiolysis of water?
ion pairs and free radicals.
What are the causes of Erythema?
individuals radiosensitivity, dose rate, size of irradiated field.
What are Chromosome Aberrations?
1. a change to the chromosome caused by radiation.
2. observed at metaphase, results when irradiation occurs early in interphase, before DNA synthesis takes place.
3. break is in the original chromosome.
what is: photon comes in and breaks a piece of the chromatid and that piece is lost forever?
deletion.
What are the rungs of the DNA ladder called, and what are they made out of?
1. base pairs
2. sugars and phosphate groups.
What is radiolysis?
dissociation of molecules by ionizing radiation.
Which phase of mitosis is the most radiosensitive?
metaphase.
Where do Chromosome Aberrations occur?
somatic cells and germ cells.
What is: chromatid gets hit and two pieces break off and switch sides?
broken end rearrangement
What type of radiation has HIGH LET?
alpha particles, ions of heavy nuclei, charged particles, low energy neutrons.
where is the hereditary information for an invidiual contained?
DNA, mainly found in the germ cells (sperm and egg cells
what component of the cell controls cell division?
the nucleus.
What are the results of Chromosome Aberrations?
1. restitution
2. deletion
3. broken end rearrangement (rings)
4. Broken end translocation.
What is: when two photons hit two different chromatids, the broken pieces of two different chromosomes come off and they switch pieces.
Broken end rearrangement Translocation
What type of radiation has LOW LET?
x-ray and gamma rays, beta particles, electrons.
What is the Radiosensitivity of an Ova?
changes over the lifetime of the egg.
what is the name of the process in which somatic cells divide?
mitosis.