radbio midterms Flashcards
Radiation causes the ionization of
(which will affect)
Atoms
Molecules
Cells
Tissues
Organ
Whole Body
Radiation interaction at the atomic level results in ________, which can produce a cell that is deficient in terms of normal _____ and ______.
molecular change
growth and metabolism
5 principal types of molecules
Lipids (fats)
Carbohydrates (sugar and starches)
Nucleic acid
Proteins
Water
organic molecules
Protein, Lipids, Carbohydrates
most critical and radiosensitive target molecule
DNA deoxyribonucleic acid
Macromolecule
DNA deoxyribonucleic acid
outside the body or outside the cell
vitro
within the living cell
vivo
When macromolecules are irradiated in vitro, that is outside the body or outside the cell, a __________ is required to produce measurable effect.
considerable radiation dose
Irradiation in vivo, that is, within the living cell, demonstrates that macromolecules are considerably __________ in their natural state.
more radiosensitive
liquid that contains dissolved substances
solution
When macromolecules are irradiated in solution in vitro, three major
effects occur:
- Main-Chain Scission
- Cross-linking
- Point Lesions
The result is the reduction of a long, single molecule into many smaller molecules, each of which may still be macromolecular.
Main-Chain Scission
It reduces not only the size of the macromolecule but also the viscosity of the solution
Main-Chain Scission
Some macromolecules have small, spur-like side structures that extend off the main chain. Other spurs as a consequence of irradiation.
Cross-linking
These side structures can behave as though they had a sticky substance on the end, and they attach to a neighboring macromolecule or to another segment of the same molecule.
Cross-linking
Radiation interaction with macromolecules also can result in disruption of single chemical bonds, producing _______.
Point Lesions
Point lesions are not detectable, but they can cause a minor medication of the molecule, which it turn can cause it to malfunction within the cell.
Point Lesions
most important molecule in the human body because it contains the genetic information for each cell
DNA
Each cell has a nucleus that contains DNA complexed with other molecules in the form of _______
chromosomes
control the growth and development of the Radiation Effects on DNA cells; these in turn determine the characteristics of the individual
chromosomes
Damage to the DNA also can result in _____
abnormal metabolic activity
principal characteristic of radiation-induced malignant disease
Uncontrolled rapid proliferation of cells
if the damage to the DNA occurs within a _____ cell, then it is possible that the response to radiation exposure will not be observed until the following generation, or even later
germ cell
most abundant component of protoplasm
water
