Phases of the cell cycle Transitional Reasoning Download PDF

Questions

1. 1.

   A research team analyzes an actively dividing, asynchronous population of human cells using flow cytometry and nucleoside analog labeling. They isolate a subpopulation of cells exhibiting an intermediate DNA content between 2C and 4C that actively incorporates bromodeoxyuridine (BrdU) into its genome. Which statement correctly identifies this specific phase of the cell cycle and describes the primary molecular event taking place within it?

   • A) G1 phase, during which the cell restores organelle numbers and initiates the condensation of chromosomes.
   • B) S phase, during which nuclear DNA is actively replicated alongside the synthesis of new histone proteins.
   • C) G2 phase, during which sister chromatids undergo crossing over while the cell synthesizes mitotic tubulin.
   • D) M phase, during which mitotic spindles pull sister chromatids to opposite poles to double the chromosome number.