Time (h) 1 3 6 12 Mouse thymus cells were treated with 10 micromolar dexamethasone to induce apoptosis. At the indicated times the chromosomal DNA was extracted and analyzed by gel electrophoresis, which separates the DNA fragments based upon size differences. When cells undergo apoptosis their DNA is cut into fragments that are approximately multiples of 200 base pairs. This results in a characteristic “ladder" appearance when the fragments are separated by gel electrophoresis, as shown above. Based upon what you know about eukaryotic chromatin, explain why this pattern of DNA fragments is obtained.

Time (h) 1 3 6 12 Mouse thymus cells were treated with 10 micromolar dexamethasone to induce apoptosis. At the indicated times the chromosomal DNA was extracted and analyzed by gel electrophoresis, which separates the DNA fragments based upon size differences. When cells undergo apoptosis their DNA is cut into fragments that are approximately multiples of 200 base pairs. This results in a characteristic “ladder" appearance when the fragments are separated by gel electrophoresis, as shown above. Based upon what you know about eukaryotic chromatin, explain why this pattern of DNA fragments is obtained.

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter28: Dna Metabolism: Replication, Recombination, And Repair

Section: Chapter Questions

Problem 12P

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