Radiation Protection In Medical Radiography: Chapter 8

A. Lymphocytes
Lymphocytes are white or colorless blood cells derived from lymphatic tissues. Because of their rapid cell division they are more susceptible to the affects of radiation.`

Which of the following types of blood cells is the most sensitive to radiation?
A. Lymphocytes
B. Granulocytes
C. Thrombocytes
D. Erythrocytes

A. Radiosensitivity will increase
Well oxygenated cells will be 2 to 3 times more radiosensitive. This is important in the radiation treatment of tumors.

How will oxygen retention effect the radiosensitivity of a cell?

A. Radiosensitivity will increase
B. Radiosensitivity will decrease
C. Radiosensitivity will be eliminated
D. Radiosensitivity will not be effected

C. Leukocyte
White blood cells divide very rapidly and therefore are very radiosensitive.

Which of the following cells would be affected by a relatively small amount of radiation exposure?

A. Muscle
B. Nerve
C. Leukocyte
D. Liver

C. Exposure to the body tissues

Somatic refers to all the cells of the body except the genetic (ova and spermatozoa) cells. Radiating the body tissues may cause changes to the somatic cells.

The somatic effects of radiation refer to which of the following?
A. Exposure to the trunk
B. Exposure to the reproductive organs
C. Exposure to the body tissues
D. Exposure to the nervous system

C. Immune system is destroyed
Since the lymphocytes are the cells that are easiest to destroy, the person will die from infection.

When radiation exposure causes hematopoietic death, what is the main reason why the person died?
A. Hemorrhage
B. Respiratory distress
C. Immune system is destroyed
D. Heart failure

C. Somatic
Somatic cells are the cells of the body that make up the tissues and organs of the individual. Genetic cells (also called germ cells) are the reproductive cells, an egg or a sperm cell.

Human cells are divided into two classifications. They are genetic cells and _______ cells.
A. Organic
B. Benign
C. Somatic
D. Reproductive

C. Lymphoid, epithelial, muscle

The most radiosensitive cells are undifferentiated and divide rapidly.

Which of following are in the correct order, going from most to least radiosensitive?
A. Epithelial, lymphoid, muscle
B. Lymphoid, muscle, epithelial
C. Lymphoid, epithelial, muscle
D. Muscle, epithelial, lymphoid

C. LET
LET = linear energy transfer. It is the rate at which energy is lost as it ionizes atoms as it passes through matter.

Which of these is a measure of the rate at which energy is transferred from radiation to soft tissue?
A. Rad
B. Erg
C. LET
D. RBE

D. 1, 2 & 3
The other possibility is that the cell will make a full recovery from any radiation damage. This is the most likely response.

Which of the following are possible results from the exposure to radiation?

1. Changes in the DNA molecule
2. Sterilization of the cell
3. Death to the cell

A. 1 only
B. 2 only
C. 1 & 3 only
D. 1, 2 & 3

D. No minimum level is known
There is no threshold dose. Even the smallest amounts of radiation exposure has the potential of harmful effects.

What is the minimum level of radiation exposure below which no genetic or somatic damage occurs?
A. 5 R
B. 10 R
C. 15 R
D. No minimum level is known

C. Complete recovery in 90 days

A human exposed to this level of radiation would experience nausea, vomiting, diarrhea and decreasing blood cell counts. However, they would be expected to completely recover.

If a human is exposed to radiation levels in the 100 to 200 R range, which of the following is expected?

A. No clinical effects
B. Slight reduction in lymphocytes
C. Complete recovery in 90 days
D. Death within 30 days

D. Bone marrow
Bone marrow is found in long bones and the flat bones of the pelvis, skull and sternum.

Irradiation of which of the following anatomical areas will affect the production of white blood cells?
A. Lungs
B. Liver
C. Pancreas
D. Bone marrow

D. Metaphase
Radiosensitive means a cell is capable of being injured or destroyed by radiation. The metaphase stage is when cells are most susceptible to radiation effects.

Which of the following stages of cell division is considered to be the most radiosensitive?
A. Prophase
B. Anaphase
C. Telophase
D. Metaphase

D. 50% of the group dies within 30 days

The amount of radiation that would kill 50% of a group within 30 days would be in the range of 400-600 rem.

What does lethal dose 50/30 mean?

A. 30 people out of 50 will die
B. 50 people will die within 30 minutes
C. 30 rem will kill half of the group
D. 50% of the group dies within 30 days

B. Nerve cells

The rate at which cells divide determines the radiosensitivity of cells. Since mature nerve cells never divide, they are least sensitive to radiation.

Which of the following mature cells would be least sensitive to radiation?
A. Muscle cells
B. Nerve cells
C. Red blood cells
D. White blood cells

B. Large dose over a short time period

A large dose over a short period of time will not allow the cells to recover from their injury, but the same dose spread over a longer time would allow recovery. This is known as fractionation.

Which of these situations will cause the greatest effect from radiation exposure?

A. Small dose over a long time period
B. Large dose over a short time period
C. Small dose over a short time period
D. Large dose over a long time period

B. Genetically significant dose
GSD stands for genetically significant dose.

What do the letters "GSD" stand for?

A. Gonadal safe dose
B. Genetically significant dose
C. Genetic-somatic dose
D. General somatic dose

A. Lymphoid tissue

Tissues are made up of cells. Tissues whose cells divide rapidly are most radiosensitive.

Which of the following is the most sensitive to radiation?

A. Lymphoid tissue
B. Epithelial tissue
C. Connective tissue
D. Muscle tissue

D. Estimated dose received by the population

GSD is an estimation of the exposure to the genetic cells of a population from all forms of radiation. It is an attempt to predict the impact of present exposure on future generations.

What does genetically significant dose mean?

A. Dose that will cause damage
B. Dose that will cause genetic damage
C. Dose that will cause a mutation
D. Estimated dose received by the population

D. Acute radiation syndrome

High-level, whole body radiation exposure, (1 Gyt) delivered in a period of seconds to minutes, produces a clinical pattern known as what?
A. Mortality irradiation
B. Cumulative exposure
C. Whole body dose
D. Acute radiation syndrome

B. Sterilization

The most common result of cell irradiation would be complete recovery. Since it is not a choice, the next most common is when the cell is damaged enough that it cannot continue to reproduce.

Which of the following is the most common result of cell irradiation?

A. Cell death
B. Sterilization
C. Mutation
D. Uncontrolled growth

A. Cells that survive an initial irradiation but produce a late effect

Stochastic effects of radiation can be defined by which of the following?
A. Cells that survive an initial irradiation but produce a late effect
B. Cells that require a threshold dose before an effect will occur
C. The greater the dose, the greater the biological effect
D. The risk of malignancy is negligible

D. 1, 2 & 3

Aberration and anomaly means departure from the normal. A lesion is a wound, injury or change in body tissue. Single-strand breaks of a DNA molecule are known as point lesions.

Gross structural changes that arise when radiation breaks a chromosome may be referred to as what?

1. Aberrations
2. Anomalies
3. Lesions

D. 1, 2 & 3

The attraction or repulsion of alpha (+) or beta (-) is more likely to interact with electrons. Particles (alpha, beta) are more likely to interact. The higher the energy the less likely an interaction.

The probability of radiation interacting with matter depends on which of the following?

1. The charge of the radiation
2. The size of the radiation
3. The energy of the radiation

B. Less than 0.01 Sv (1 rem)

Most diagnostic procedures result in equivalent doses:

A. Above 0.01 Sv (1 rem)
B. Less than 0.01 Sv (1 rem)
C. Above 1.56 Sv (156 rem)
D. Between 0.01 Sv and 1.56 Sv (1 rem and 156 rem)

B. Leukemia

According to data from studies performed on U.S. Radiologic Technologists, individuals who began working before 1950 had a somewhat higher risk of dying from __________ when compared with technologists who started working in 1950 and later.

A. Darkroom disease
B. Leukemia
C. Pancreatic cancer
D. Thyroid cancer

C. Induction of cancer

Early demise of experimental animals exposed to nonlethal doses of ionizing radiation actually resulted from:

A. Accelerated aging
B. Hemorrhage
C. Induction of cancer
D. Respiratory distress

B. Dramatic increase in thyroid cancer in children living in the regions where the heaviest radioactive contamination occurred

During the 10 years immediately after the 1986 Chernobyl nuclear power station accident, which of the following was the most pronounced health effect observed?

A. Dramatic increase in the incidence of childhood leukemia
B. Dramatic increase in thyroid cancer in children living in the regions where the heaviest radioactive contamination occurred
C. Major increase in the number of solid tumors in the general population of the former Soviet Union

B. Gamma radiation exposure

Reevaluation of the quantity and type of radiation that was released in the atomic bombing of the cities of Hiroshima and Nagasaki has led to revised atomic bomb data in which radiation-induced leukemia and solid tumors may now be attributed predominantly to :

A. Alpha radiation exposure
B. Gamma radiation exposure
C. Neutron radiation exposure
D. X-radiation exposure

A. Directly proportional to the dose

The linear nonthreshold curve implies that biologic response is:

A. Directly proportional to the dose
B. Inversely proportional to the dose
C. Insignificant in relation to dose
D. Not able to be plotted on a dose-response curve

A. Data from human populations observed after acute high doses of radiation

Which of the following provide the foundation for the sigmoid or "S-shaped" (non-linear) threshold curve of radiation dose response?

A. Data from human populations observed after acute high doses of radiation
B. Data from human populations observed after chronic low doses of radiation
C. Laboratory experiments on animals

1, 2, & 4

Some examples of measurable late biologic damage are:

1. Cataracts
2. Leukemia
3. Nausea and vomiting
4. Genetic mutations

A. Stochastic

Cancer and genetic defects are examples of __________ effects.

A. Stochastic
B. Nonstochastic
C. Birth
D. Deterministic

1, 2, & 3

Which of the following groups provide evidence for radiation carcinogenesis?

1. Radium watch dial painters (1920s and 1930s)
2. Early medical radiation workers (1896 to 1910)
3. Japanese atomic bomb survivors (1945)

A. Technologists who began working before 1940

Members of which of the following groups of radiologic technologists have the greatest risk of dying from breast cancer as a consequence of their occupation?

A. Technologists who began working before 1940
B. Technologists who began working after 1950
C. Women employed as technologists after 1960
D. Women employed as technologists after 2000

B. Measurable radiation-induced biologic damage

Cataracts, leukemia, and genetic mutations are examples of:

A. Diseases that are not caused by ionizing radiation
B. Measurable radiation-induced biologic damage
C. Diseases caused by nonionizing radiation
D. Radiation-induced biologic damage that cannot be measured

A. Animal studies of radiation-induced genetic effects

Which of the following led to the development of the doubling dose concept?

A. Animal studies of radiation-induced genetic effects
B. Human studies of radiation-induced genetic effects
C. Animal studies of radiation-induced somatic effects
D. Human studies of radiation-induced somatic effects

D. Extensive experiments with fruit flies and mice at high radiation doses

The only concrete evidence that ionizing radiation causes genetic effects comes from:

A. Human populations exposed to low radiation doses
B. Human populations exposed to moderate radiation doses
C. Human populations exposed to high radiation doses
D. Extensive experiments with fruit flies and mice at high radiation doses

D. Cancer and genetic defects

Which of the following are examples of stochastic effects?

A. Nausea and vomiting
B. Epilation and fatigue
C. Diarrhea and leukopenia
D. Cancer and genetic defects

C. 400,000

After the Chernobyl nuclear power plant accident in 1986, approximately how many people worldwide received some exposure to fallout?

A. 100,000
B. 250,000
C. 400,000
D. 900,000

D. Thyroid cancer

After the accident at the Chernobyl nuclear power plant in 1986, many children in Poland and some other countries were given potassium iodide in an attempt to prevent:

A. Breast cancer
B. Bone cancer
C. Leukemia
D. Thyroid cancer

1, 2, & 3

Which of the following types of cells develop from a single precursor cell, the pluripotential stem cell?

1. Lymphocytes and granulocytes
2. Thrombocytes and erythrocytes
3. Platelets

C. Multiply to millions of cells only during fetal development, before birth, and then steadily decline in number throughout life

In the female, the ovarian stem cells:

A. Begin as a single cell during fetal development, before birth, and then gradually increase in number throughout life
B. Multiply to a few hundred cells during fetal life, before birth, and then gradually increase in number throughout life
C. Multiply to millions of cells only during fetal development, before birth, and then steadily decline in number throughout life
D. Multiply to millions of cells only during fetal development, before birth, and then steadily continue to increase in number throughout life

A. William Herbert Rollins

In 1898, after developing burns attributed to radiation exposure, this Boston dentist began investigating the hazards of radiation exposure and became the first advocate of radiation protection. Who is this person?

A. William Herbert Rollins
B. Wilhelm Conrad Roentgen
C. Thomas Alva Edison
D. Clarence Madison Dally

D. Production of chromosome aberrations

The total radiation dose received by a somatic or genetic cell and the dose rate determine the:

A. Cell growth reduction rate
B. Cause of chromosome aberrations
C. Mechanism of action of ionizing radiation on biologic macromolecules
D. Production of chromosome aberrations

D. 90%, 10%

When cells are exposed to sublethal doses of ionizing radiation, approximately ____ of radiation-induced damage may be repaired over time, and about ____ is irreparable.

A. 25%, 75%
B. 50%, 50%
C. 75%, 25%
D. 90%, 10%

C. Hematopoietic

Which of the following systems is the most radiosensitive vital organ system in human beings?

A. Cerebrovascular
B. Gastrointestinal
C. Hematopoietic
D. Skeletal

B. LD 50/60

Most accurate/relevant indicator of outcome

Lethal dose of ionizing radiation for humans is usually given as:

A. LD 50/30
B. LD 50/60
C. LD 50/90
D. LD 50/120

3

The use of high-level fluoroscopy for extended periods of time can result in which of the following in patients?

1. Acute radiation syndrome
2. Repair of damaged chromosomes
3. Radiation-induced skin injuries

1, 2, & 3

Some local tissues experience immediate consequences from high radiation doses. Which of the following are examples of such tissues?

1. Bone marrow
2. Male and female reproductive organs
3. Skin

C. Exposure to high-level radiation

ARS is actually a collection of symptoms associated with:

A. Exposure to low-level radiation
B. Exposure to moderate-level radiation
C. Exposure to high-level radiation
D. Exposure to nonionizing radiation

A. During the fetal stages of life and during early childhood

When are the ovaries of the human most radiosensitive?

A. During the fetal stages of life and during early childhood
B. After puberty and the onset of menstruation
C. From 20 to 30 years of age
D. During pregnancy

B. There is a difference in the way in which male and female germ cells are produced and progress

The testes of the human male and the ovaries of the female do not respond the same way to irradiation because:

A. The oogonia, the ovarian stem cells of the female, constantly reproduce throughout life
B. There is a difference in the way in which male and female germ cells are produced and progress from elementary stem cells to mature cells
C. The oogonia become encapsulated by numerous primordial follicles during development
D. The spermatogonia of the male never mature

B. Contain a repair mechanism inherent in their biochemistry (repair enzymes)

When cells are exposed to sublethal doses of ionizing radiation, repair and recovery may occur because cells:

A. Are completely insensitive to radiation exposure
B. Contain a repair mechanism inherent in their biochemistry (repair enzymes)
C. Exposed to sublethal doses become hypoxic and recover more efficiently
D. Mutate and become radioresistant

C. Stage called manifest illness

Infection, hemorrhage, and cardiovascular collapse are symptoms that can occur as part of acute radiation syndrome during the:

A. Initial stage
B. Latent period
C. Stage called manifest illness
D. Recovery

C. 3.0 to 4.0 Gy (300 to 400 rad)

Without medical support, the LD 50/30 for adult humans is estimated to be:

A. 1.0 to 2.0 Gy (100 to 200 rad)
B. 2.0 to 3.0 Gy (200 to 300 rad)
C. 3.0 to 4.0 Gy (300 to 400 rad)
D. 4.0 to 5.0 Gy (400 to 500 rad)

D. Occurrence of nausea and vomiting

Without effective physical monitoring devices, what biologic criteria would play an important role in the identification of radiation casualties during the first 2 days after a nuclear disaster?

A. Coma
B. Edema in the cranial vault
C. Meningitis
D. Occurrence of nausea and vomiting

D. Total-body syndrome

The hematopoietic, gastrointestinal, and cerebrovascular syndromes are three separate dose-related syndromes that are part of the:

A. Bone marrow syndrome
B. Cytogenetic syndrome
C. Prodromal syndrome
D. Total-body syndrome

1, 2, & 3

Which of the following factors govern organ and tissue response to radiation exposure?
1. Growth rate
2. Radiosensitivity
3. Reproductive characteristics

C. Radiation-induced skin injuries for patients

The use of high-level fluoroscopy for extended periods of time can result in:

A. A significant reduction in radiation-induced skin injuries for patients
B. Minimal total-body radiation exposure for patients
C. Radiation-induced skin injuries for patients
D. The need for all patients to have periodic blood counts to monitor radiation dose received

D. Small intestine

In humans with the gastrointestional form of ARS, the part of the body most severely affected is the:

A. Brain
B. Heart
C. Large intestine
D. Small intestine

1, 2, & 3

On which of the following factors does somatic or genetic radiation-induced damage depend?

1. The amount of body area exposed
2. The quantity of ionizing radiation to which the subject is exposed
3. The specific parts of the body exposed

D. Radiodermatitis

Many early radiologists and dentists developed a reddening of the skin caused by exposure to ionizing radiation. This condition is called:

A. Dermabrerration
B. Desquamation
C. Epidermatitis
D. Radiodermatitis

D. 400 to 500

During the age of approximately 12 to 50, how many mature ova will a female produce?

A. 50 to 100
B. 100 to 200
C. 300 to 400
D. 400 to 500

C. Karyotype

A cytogenetic analysis of chromosomes may be accomplished through the use of a chromosome map. This map is called a:

A. Chromosomogram
B. Karyograph
C. Karyotype
D. Photocytogenetic plot

A. 2%

Approximately what percent of the human body's surface skin cells are replaced daily by stem cells from an underlying basal layer?

A. 2%
B. 12%
C. 35%
D. 50%

A. Deterministic

When biologic effects from ionizing radiation demonstrate the existence of a threshold and the severity of that damage increases as a consequence of increased absorbed dose, the events are considered:

A. Deterministic
B. Probabilistic
C. Stochastic
D. Unimportant

C. Greatest reproductive activity, longest mitotic phases, and least maturity

With respect to the law of Bergonie and Tribondeau, which of the following would best complete this statement? "The most pronounced radiation effects occur in cells having the __________."

A. Least reproductive activity, shortest mitotic phases, and most maturity
B. Greatest reproductive activity, shortest mitotic phases, and most maturity
C. Greatest reproductive activity, longest mitotic phases, and least maturity
D. Least reproductive activity, shortest mitotic phases, and least maturity

B. When two direct hits occur in the same rung of the DNA macromolecule

When does ionizing radiation cause complete chromosome breakage?

A. When a single strand of the sugar-phosphate chain sustains a direct hit
B. When two direct hits occur in the same rung of the DNA macromolecule
C. When two direct hits occur in different rungs of the DNA macromolecule
D. When two direct hits are sustained at opposite ends of the DNA macromolecule

1, 2, & 3

Of the following blood cell producing organs, which are considered radiosensitive?

1. Spleen
2. Bone marrow
3. Lymphatic nodes

B. Thyroid cancer

Early radiation therapy treatments for acne and tonsillitis has resulted in some cases of what?

A. Death
B. Thyroid cancer
C. Brain damage
D. Pineal calcification

D. Bone marrow

Irradiation of which of the following anatomical areas will affect the production of white blood cells?

A. Lungs
B. Liver
C. Pancreas
D. Bone marrow

A. Prenatal death

What would be the probable result of any major radiation exposure during the first few days of pregnancy?

A. Prenatal death
B. Postnatal death
C. A child with genetic deficiencies
D. A normal birth and infant

B. The gene

Which of the following is considered the unit of heredity?

A. The cell
B. The gene
C. The chromosome
D. The DNA molecule

C. Gonads

Which of the following organs is considered radiosensitive?

A. Liver
B. Spleen
C. Gonads
D. Thyroid

C. Immune system is destroyed

Since the lymphocytes are the cells that are easiest to destroy, the person will die from infection.

When radiation exposure causes hematopoietic death, what is the main reason why the person died?

A. Hemorrhage
B. Respiratory distress
C. Immune system is destroyed
D. Heart failure

B. A mutation can increase cell growth

Cancer is the rapid growth of a tissue. A change in the DNA molecule can be the reason for this rapid cell division.

How can radiation induce cancer in a person?

A. It can alter a cells function
B. A mutation can increase cell growth
C. It can cause cell death
D. Radiation destroys the immune system

A & C

Stochastic effects of radiation can be defined by which of the following? (Multiple answers)

A. Cells that survive an initial irradiation but produce a late effect
B. Cells that require a threshold dose before an effect will occur
C. The greater the dose, the greater the biological effect
D. The risk of malignancy is negligible

C. 300 to 400 R

For humans to receive an exposure large enough to kill 50% of them within 60 days there would have to be a nuclear accident (like Chernobyl) or nuclear war.

How much radiation exposure does it take to have a lethal dose where 50% of the humans would die within 60 days?

A. 100 to 200 R
B. 200 to 300 R
C. 300 to 400 R
D. 400 to 500 R

2 only

Radiation exposure to the gonads (sperm & ova) may alter the genetic code in the DNA molecule and cause a mutation in future generations. A radiation induced mutation is always bad!

Why is radiation exposure to the gonads such a critical concern?

1. The person may become sterile
2. Mutations in offspring may result
3. Gonadal cancer may develop

B. But successful results have not been achieved in these studies

Attempts have been made to measure chromosome aberrations after diagnostic x-ray imaging procedures:

A. And these studies have been very successful in measuring the number of chromosome aberrations that occurred
B. But successful results have not been achieved in these studies
C. But these studies have only been moderately successful in measuring the number of chromosome aberrations that occurred
D. But these studies have only been minimally successful in measuring the number of chromosome aberrations that occurred

D. 0.25; 25

Genetic mutations have been produced in experimental female animals when their ovaries were irradiated with doses as low as _____ Gy (_____ rad).

A. 0.10; 10
B. 0.15; 15
C. 0.20; 20
D. 0.25; 25

D. 0.5; 50

A decrease in the number of neutrophils can be caused by a radiation dose of _____ Gy (_____ rad).

A. 0.1; 10
B. 0.2; 20
C. 0.3; 30
D. 0.5; 50

A. Cumulative

Research has shown that repeated radiation injuries have a _____ effect.

A. Cumulative
B. Quadratic
C. Sigmoidal
D. Threshold

Excessive nervousness, confusion, severe nausea and vomiting

What are some symptoms of the cerebrovascular syndrome?

A. 0.25

In the years when periodic blood counts were used for radiation monitoring purposes, a whole-body dose as low as _______ Gyt would produce a measurable hematologic depression

A. 0.25
B. 0.30
C. 0.5
D. 0.55

C. 2

A single absorbed dose of _____ Gyt can cause radiation-induced skin erythema within 24 hours to 48 hours after irradation

A. 6
B. 4
C. 2
D. 10

D. All of the above

Possible high radiation dose consequences that would result from exposure of the whole body two types of radiation other than xray include which of the following?

A. Blood disorders
B. Epilation
C. Intestinal disorders
D. All of the above

A. Cumulative

Research has shown that repeated radiation injuries have a _____ effect.

A. Cumulative
B. Quadratic
C. Sigmoidal
D. Threshold

Prodromal period

The immediate response to radiation that includes signs and symptoms of radiation sickness

Nausea, vomiting, diarrhea, reduction of WBC

1Gyt or 100 RAD

Lasts hours-days

Latent period

The time after exposure during which there is no sign of radiation sickness and is a time of apparent well-being that may be mistakenly seen as early recovery

Lasts about a week

At doses of about 6 Gyt

Hematologic death

Gastrointestinal death

Central nervous system death

Lethal syndrome that is caused by lower doses (2-10 Gy, 200-1000 rad) and takes hours to occur?

Lethal syndrome that is caused by doses from 10 to 50 Gyt or 1000 to 5000 Rad and occurs within a few days?

Lethal syndrome that is caused by doses above 50 Gyt or 5000 Rad and occurs within hours?