NMT 3210 EXAM QUESTIONS AND ANSWERS
How long does it take for a cell to repair? - Answers - 24 hours
The more non-differentiated
or actively dividing a cell is,
the more radiosensitive it is
and... The more differentiated or
mitotically fixed a cell is,
the more radioresistant it is.
Except mature
lymphocytes. - Answers - Direct and Indirect effects
summed up in Law of Bergonie
and Tribondeau
-All or none response to
radiation: random or
statistical
-No threshold - can result
from a single interaction
-Probability increases with
dose
-Severity does not increase
with dose - Answers - Stochastic effect
-Collective injury to a number
of cells
-Non-linear w/Known
thresholds
-Severity of effect increases
with dose - Answers - Deterministic effect
___________ effect examples are Cancer, Leukemia, Genetic damage appears in
offspring - Answers - stochastic
Stochastic effects can have long latent periods. Therefore, also known as - Answers -
Late effects
______-______ rem enough to cause effect on embryo - Answers - 5-15
Fetus is generally less radiosensitive after week _____ - Answers - 20
______ Trimester is most sensitive - Answers - 1st
Occupational dose limit to fetus is _____ rem/ gestation - Answers - 0.5
, What kind of exposure is a High dose of radiation delivered
within a short time: 500 rem for 10 sec? (also deterministic) - Answers - Acute
Short term Deterministic are seen as - Answers - early effects
erythema - skin reddening (sunburn), depilation - hair loss, blood changes, diarrhea,
fever are signs of _________ effects - Answers - early
ataracts, fibrosis, degenerative diseases are signs of _______ term and
______________ effects - Answers - Long, deterministic
Acute Effects are also______________ ____________
-Whole body
-High level exposure >100rads
-Lethal/near lethal syndromes (Hematologic or BMS, Gastrointestinal,CNS) - Answers
- Early effects
-Results from damage to the stem cells in the bone marrow and
lymphatic organs
-usually occurs above doses of 2 Gy/200 rad
-results in infections and hemorrhage due to granulo- and
thrombocytopenia.
-Death occurs within 4-5 weeks
Acute (100-1000 rad (1000 lethal), Prodromal stage: nausea vomiting, Latent period 3-5
weeks, Manifest illness: lose WBC/RBC forming
capacity, Die from infection, electrolyte imbalance) - Answers - The Hematopoietic
Syndrome (Bone Marrow Syndrome BMS)
-Occurs when doses exceed 6 Gy/600rad
-Loss of intestinal stem cells leads to a breakdown of the intestinal/vascular barrier
-Sepsis and death within 5-8 days.
Acute (600-5000 rad, Prodromal stage: nausea/vomiting/diarrhea, Latent period 5 days,
Manifest illness: lose lining of GI tract, Die from dehydration, sepsis) - Answers - The
Gastrointestinal Syndrome (GIS)
characterized by immediate onset of severe neurological changes following massive
exposures of over 50 Gy/5000rad. convulsions and death within 2 days
Acute (>5000 rad, Prodromal stage: nausea vomiting w/in minutes, Latent period few
hours, Manifest illness: convulsions, ataxia, breathing difficulty, coma, Die from
increased cranial pressure) - Answers - The Central Nervous System Syndrome
(CNSS)
occupational dose limit for whole body? (in rem) - Answers - 5 rem/year
How long does it take for a cell to repair? - Answers - 24 hours
The more non-differentiated
or actively dividing a cell is,
the more radiosensitive it is
and... The more differentiated or
mitotically fixed a cell is,
the more radioresistant it is.
Except mature
lymphocytes. - Answers - Direct and Indirect effects
summed up in Law of Bergonie
and Tribondeau
-All or none response to
radiation: random or
statistical
-No threshold - can result
from a single interaction
-Probability increases with
dose
-Severity does not increase
with dose - Answers - Stochastic effect
-Collective injury to a number
of cells
-Non-linear w/Known
thresholds
-Severity of effect increases
with dose - Answers - Deterministic effect
___________ effect examples are Cancer, Leukemia, Genetic damage appears in
offspring - Answers - stochastic
Stochastic effects can have long latent periods. Therefore, also known as - Answers -
Late effects
______-______ rem enough to cause effect on embryo - Answers - 5-15
Fetus is generally less radiosensitive after week _____ - Answers - 20
______ Trimester is most sensitive - Answers - 1st
Occupational dose limit to fetus is _____ rem/ gestation - Answers - 0.5
, What kind of exposure is a High dose of radiation delivered
within a short time: 500 rem for 10 sec? (also deterministic) - Answers - Acute
Short term Deterministic are seen as - Answers - early effects
erythema - skin reddening (sunburn), depilation - hair loss, blood changes, diarrhea,
fever are signs of _________ effects - Answers - early
ataracts, fibrosis, degenerative diseases are signs of _______ term and
______________ effects - Answers - Long, deterministic
Acute Effects are also______________ ____________
-Whole body
-High level exposure >100rads
-Lethal/near lethal syndromes (Hematologic or BMS, Gastrointestinal,CNS) - Answers
- Early effects
-Results from damage to the stem cells in the bone marrow and
lymphatic organs
-usually occurs above doses of 2 Gy/200 rad
-results in infections and hemorrhage due to granulo- and
thrombocytopenia.
-Death occurs within 4-5 weeks
Acute (100-1000 rad (1000 lethal), Prodromal stage: nausea vomiting, Latent period 3-5
weeks, Manifest illness: lose WBC/RBC forming
capacity, Die from infection, electrolyte imbalance) - Answers - The Hematopoietic
Syndrome (Bone Marrow Syndrome BMS)
-Occurs when doses exceed 6 Gy/600rad
-Loss of intestinal stem cells leads to a breakdown of the intestinal/vascular barrier
-Sepsis and death within 5-8 days.
Acute (600-5000 rad, Prodromal stage: nausea/vomiting/diarrhea, Latent period 5 days,
Manifest illness: lose lining of GI tract, Die from dehydration, sepsis) - Answers - The
Gastrointestinal Syndrome (GIS)
characterized by immediate onset of severe neurological changes following massive
exposures of over 50 Gy/5000rad. convulsions and death within 2 days
Acute (>5000 rad, Prodromal stage: nausea vomiting w/in minutes, Latent period few
hours, Manifest illness: convulsions, ataxia, breathing difficulty, coma, Die from
increased cranial pressure) - Answers - The Central Nervous System Syndrome
(CNSS)
occupational dose limit for whole body? (in rem) - Answers - 5 rem/year
