THE EFFECT OF MITOTIC CYCLE DURATION OF CHROMOSOME BREAKAGE IN MERISTEMATIC CELLS OF PISUM SATIVUM

Journal Article · Fri Nov 01 04:00:00 EST 1963 · Proc. Natl. Acad. Sci. U.S.

DOI:https://doi.org/10.1073/pnas.50.5.855· OSTI ID:4149181

Van't Hof, J; Sparrow, A H

Experiments were performed with seedlings of Pisum sativum to test the hypothesis that radiosensitivity with respect to chromosome damage increases during chronic irradiation with increased mitotic cycle time. Minimum cycle times were determined for root meristem cells. Temperatures of 30, 25, 15, and 10 deg C were used to obtain different minimum cycle times. The results of chronic exposures indicated that the minimum cycle time was not altered in Pisum sativum until the total exposure per cycle exceeded about 440-450 r; the percentage of cells showing damaged chromosomes at a stated daily exposure rate increased with decreasing temperatures if mitotic cycle time was not considered; but when the cycle time is taken into account, the production of damaged cells is a linear function of the amount of total exposure per mitotic cycle up to the critical value 440-450 r/cycle. (auth)

• Research Organization: Brookhaven National Lab., Upton, N.Y.
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-001417
• OSTI ID: 4149181
• Journal Information: Proc. Natl. Acad. Sci. U.S., Journal Name: Proc. Natl. Acad. Sci. U.S. Vol. Vol: 50
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

AGE
BIOLOGY AND MEDICINE
CHROMOSOMES
CYTOLOGY
MITOSIS
PISUM SATIVUM
PLANTS
QUANTITY RATIO
RADIATION DOSES
RADIATION EFFECTS
RADIOSENSITIVITY
ROOTS
SEEDS
TEMPERATURE
VARIATIONS
VEGETABLES