Ouhsc Radiobiology Test 1

Front 1

when did Roentgen discover x-rays

Back 1

1895

Front 2

who discovered the emission of radioactivity from uranium in 1896

Back 2

Becquerel

Front 3

who left a radium container in his vest pocket

Back 3

Becquerel

Front 4

who attempted to repeat the skin exposure by producing a radium burn in their forearm

Back 4

curie

Front 5

define radiobiology

Back 5

the stufy of the action of ionizing radiation on living things

Front 6

who siad that the resistance or sensitivity to radiation depends on the metabolic state of a cell,

Back 6

Bergonie and Tribondeau

Front 7

which forms of electromagnetic radiation have the capability of acting like they have mass (but do not actually have mass)

Back 7

x-ray and gamma

Front 8

what type of radiation actually has mass

Back 8

particulate radiaiton

Front 9

what 3 types of electromagnetic radiation are ionizing

Back 9

x-rays, gamma rays, and cosmic rays

Front 10

name the 8 types of electromagnetic radiaiton

Back 10

x-ray
gamma
cosmic
visible light
ultraviolet
infrared
microwaves
radio waves

Front 11

on the electromagnetic spectrum, the ionizing radiations have a high or low frequency

Back 11

high frequency

Front 12

______ and _______behave as waves when traveling through space

Back 12

X-ray and gamma photons

Front 13

When ____ and _____ encounter matter, they take on the characteristics of particles

Back 13

x-rays and gamma rays

Front 14

name 3 souces of radiation

Back 14

natural sources
medical sources
nuclear sources

Front 15

________ is wavelike fluctuations of electric and magnetic fields &/or photons

Back 15

electromagnetic radiaiton

Front 16

Electromagnetic waves have properties of ____ and _____

Back 16

frequency and wavelength

Front 17

how is frequency measured

Back 17

in cycles per second - measured in Hz

Front 18

wavelength is the _______

Back 18

distance between two successive points on a wave

Front 19

x-ray wavelength is very (long or short), and is measured in

Back 19

short
Angstroms 1x10-10 meters

Front 20

one angstrom is equal to ______

Back 20

1x10-10 meters

Front 21

All electromagnetic radiation moves at _______

Back 21

the speed of light

Front 22

what is the speed of light

Back 22

3x10 ^ 8 m/s

Front 23

wavelength, frequency, and the speed of light are represented by what symbols

Back 23

wavelength = lambda
frequency = v
speed of light = c

Front 24

with x-ray and gamma, the wavelength is very _____ so the frequency must be very ______

Back 24

small
large

Front 25

the higher the energy, the higher the (wavelength or frequency)

Back 25

frequency

Front 26

in order of least penetrating to most penetrating, list the following.
gamma
neutrons
alpha
beta

Back 26

alpha
beta
gamma
neutrons

Front 27

what happens during excitation

Back 27

the electrons in am atom are raised to an excited state, with out the actual ejection of an electron

Front 28

what happens during ionization

Back 28

when a radiaiton has been absorbed into an atom and it has sufficient energy to cause the ejection of an orbital electron

Front 29

when a tissue absorbs radiation and the chain of events that leads t biological change is initiated, this is called

Back 29

direct ionization

Front 30

when radiaiton reacts with atoms or molecules in a cell (particularly water) and produces free radicals that are able to difuse far enough to reach and damage critical targets, this is called

Back 30

indirect ionization

Front 31

When low energy photons (~10 keV) interact with atoms, they do not possess the energy necessary to eject an orbital electron.
whta type of interaction does this describe?

Back 31

coherent scatter

Front 32

describe what happens during coherent scatter

Back 32

radiaiton is absorbed by an atom, it becomes excited, and a secondary photon is then released having the same energy and wavelength as the incident photon but traveling in a different direction.

Front 33

describe what happens during photoelectric interaction

Back 33

An incident photon with moderate energy enters an atom and gives up all of its energy to eject a bound orbital electron as a photoelectron.
The atom is now ionized and in an excited state.
An electron from a higher energy shell then fills the hole left by the photoelectron with resultant emission of a characteristic photon.

Front 34

during photoelectrin interaction, give the formula for finding the energy of the photoelectron that was produced

Back 34

energy of the photoelectron = the energy of the incident photon - the binding energy

Front 35

during photoelectric interaction, the characteristic photon has an energy that is __________

Back 35

equal to the difference in orbital shell energies.

Front 36

with photoelectric interaction, the characteristic photons that are emitted have (low or high) energy. what happens to them

Back 36

low energy and are absorbed close to the area they are produced

Front 37

describe what happens during a compton interaction

Back 37

A moderate energy incident photon ejects an outer shell electron giving up some of its energy.
This causes the photon to change direction or ”scatter”.
The ejected or recoil electron can then go fill a shell vacancy in another atom or ionize surrounding tissue if it has the necessary energy to eject an orbital electron.

Front 38

describe whta happens during pair production

Back 38

A high energy photon (at least 1.02 MeV) enters an atom, interacts with the nuclear force field, and is converted to 2 charged particles, a negatron and a positron, each having an equal amount of energy.
As each particle continues, it may encounter another particle of the opposite charge and produce 2 photons traveling in opposite directions and each having energy equaling half of the incident photon.

Front 39

describe what happens during photodisintigration

Back 39

A very high energy photon (at least 10 MeV) interacts directly with the nucleus of an atom.
The nucleus absorbs the energy from the photon, is raised to an excited state, and then emits a nucleon or other nuclear fragment.

Front 40

with moderate energy incident radiation, the probability of Compton interaction increases as the x-ray energy ______

Back 40

increases

Front 41

with high energy incident radiation the type of interaction that occurs depends on whether the energy is large enough to do what

Back 41

large enough to disrupt the nucleus.

Front 42

this is the number of ion pairs produced per unit length of path. Usually per cm.

Back 42

specific ionization

Front 43

this is the rate of energy deposition per unit length of path

Back 43

LET

Front 44

LET is expresssed as

Back 44

Expressed as keV per micron (10^6 m)

Front 45

what are some high LET radiations

Back 45

neutrons
protons
alpha particles

Front 46

what are some low LET radiations

Back 46

x-ray
gamma rays
beta particles
electrons

Front 47

results in the affected cellular system not working or being modified. this describes a _______

Back 47

mutation.

Front 48

what does the term direct action mean

Back 48

If it gets hit by radiation, it’s damaged. it involves the interaction with macromolecules and the breakage of chemical bonds, protein chains, etc.

Front 49

direct action interactions are most likely to occur with particles having (hihg or low) LET

Back 49

high LET

Front 50

the target theory involves the (direct or indirect) action

Back 50

direct action

Front 51

describe indirect aciton

Back 51

the result of damage by free radicals produced as a result of radiolysis of water.
water gets broken into ionized components producing radicals which can recombine to make hydrogen peroxide.

Front 52

with indirect action, the water in cells is turned into _____, which is toxic to cells

Back 52

H2O2
hydrogen and hydroxyl

Front 53

Free radicals are another product of ________ that are highly reactive and capable of causing changes to solute molecules.

Back 53

radiolysis

Front 54

_______ contain DNA but no nucleus

give an example

Back 54

Prokaryotes –
bacteria

Front 55

with _______ the DNA is contained in nucleus

give an example

Back 55

Eukaryotes
Single & multicellular organisms

Front 56

what are the 4 cell componants

Back 56

Cell membrane
Cytoplasm
Cytoskeleton
Organelles

Front 57

what cell componant is responsible for cell packaging

Back 57

cell membrane

Front 58

the cell membrane copntains a lipid bilayer. Each molecule has one end that is ________, and one end that is _________
.

Back 58

hydrophilic
hydrophobic

Front 59

the _______ provides structure and assists in cell movement

Back 59

Cytoskeleton

Front 60

Filaments and microtubules
are contained in what part of the cell

Back 60

cytoplasm

Front 61

name the 8 types of organells

Back 61

Nucleus
Mitochondria
Ribosomes
Endoplasmic reticulum
Golgi
Lysosomes
Peroxisomes
Endosomes

Front 62

_____ inolvolves:
Increasing cell numbers
Duplicate copies
Important for tissue growth & cell replacement

Back 62

mitosis

Front 63

______ involves:
Producing germ cells
Not all identical
Can carry mutations from parent to offspring

Back 63

meosis

Front 64

the protein synthesis descibed is ________.

DNA template used to make mRNA

Back 64

transcription

Front 65

what regulates the time and amount of DNA transcribed

Back 65

transcription factors

Front 66

the protein synthesis described is ________

mRNA used by ribosomes to construct amino acids and proteins

Back 66

translation

Front 67

_______ can be used for cellular function or packaged for transport out of the cell

Back 67

synthesized proteins

Front 68

describe the DNA structure

Back 68

double helix of alternating sugar and phosphate groups having 1 of 4 bases attached to the deoxyribose sugar

Front 69

what are the 2 Purines

Back 69

adenine & guanine

Front 70

what are the 2 Pyramidines

Back 70

thymine and cytosine