D8 Nuclear medicine

Question 1

define nucleons

Answer 1

number and type of nucleons present

protons and neutrons

Question 2

stable vs unstable nuclei

Answer 2

balanced forces among nucleons // unbalanced forces

not reactive // radioactive (spontaneously decay - forms more stable nuclei)

Question 3

what are unstable nuclei called

Answer 3

radionuclides

Question 4

describe natural radionuclides

Answer 4

• occur in enviro
• include 235U, 3H, 14C
• all elements Z=84 and above = naturally radioactive, no stable naturally occuring isotope

Question 5

describe induced/artificial radionuclides

Answer 5

• unstable thru procedures, usually bombardment reactions w neutrons/helium nuclei at great speed
• many radionuclides used in nuclear med prod thru this

Question 6

how are most radionuclides in nuclear med produced

Answer 6

induced/artificial radionuclides
- made unstable usually thru bombardment reactions with neutrons/helium nuclei at great speed

Question 7

define radioactivity

Answer 7

involves the emission of energy and particles
from the nucleus as
an atom decays
into a more stable form

Question 8

who discovered radioactivity (initial)

Answer 8

henri becquerel
- photographic plates became fogged close to uranium salts – bc emission

Question 9

who furthered radioactivity studies

Answer 9

pierre and marie curie

Question 10

2 types of atomic nuclei

Answer 10

1. quarks – makes up neutrons and protons
2. antiparticles – equivalent mass but opp charge eg positron

Question 11

how are quarks arranged

Answer 11

sets of 3

Question 12

what is a positron

Answer 12

antiparticle of an electron w same pass and positive charge
- when antiparticles and particles collide = mutual destruction

Question 13

5 possible events during the decay of a radionucleotide into a more stable form

Answer 13

1. ejection of a neutron
2. ejection of a proton
3. conversion of. aneutron to a proton + ejection of beta particle
4. conversion of proton to neutron + ejection of positron
5. release of gamma rays

Question 14

what is ejected when a neutron is converted to a proton

Answer 14

beta particle

Question 15

what is ejected when a proton is converted to a neutron

Answer 15

a positron

Question 16

results of radionuclide decay 3

Answer 16

1. diff types of radiation
2. formation of new nuclide
3. change in proton number

Question 17

what is alpha radiation

Answer 17

the ejection of particles from the nucleus that carry a charge of 2+ and have a mass of 4 atomic mss units

Question 18

alpha radiation is equivalent to a nucleus of ______, can be denoted as ^4 v2 __ or ^4 v2 a

Answer 18

helium
He

Question 19

emission of an alpha particle causes the mass number of a radionuclide to ____ by __ units and atomic number to ____ by __ units

Answer 19

decrease
4
decrease
2 `

Question 20

example of alpha decay – uranium to ?

Answer 20

thorium
238 –> 234
92 –> 90

Question 21

what is beta radiation

Answer 21

conversion of a neutron to a proton with ejection of an electron (beta particle)

OR

converstion of a proton to a neutron with ejection of an positron

Question 22

beta radiation example tritium –> ?

Answer 22

helium
- emission of a beta particle and a neutrino

Question 23

what is gamma radiation (γ)

Answer 23

emission of energy as electromagnetic waves (photons)

Question 24

what is the wavelength of photons

Answer 24

very short!
0.0005-0.1nm

Question 25

frequencies of gamma radiation

Answer 25

above 10^19 Hz

Question 26

does gamma radiation involve altered atomic or mass number

Answer 26

NO. it results from energy changes in the nucleus

Question 27

what does gamma radiation result from

Answer 27

results from energy changes in the nucleus

Question 28

gamma radiation often accompanies ____________ as the energy of the _________ is ________ during radioactive decay

Answer 28

alpha or beta raditaion

radionuclide

lowered

Question 29

what usually accompanies alpha or beta radiation

Answer 29

gamma radiation