OCR GCSE Biology 2026 – 400 Free Practice Questions to Pass the Exam

The term 'chromosome' during mitosis refers to a structure containing DNA in an organized form. In this phase of the cell cycle, chromosomes become highly condensed and visible under a microscope, allowing them to be accurately separated into daughter cells. Each chromosome consists of DNA tightly coiled around proteins called histones, ensuring that the genetic material can be efficiently managed and distributed during cell division. This organization is crucial, as it helps prevent the tangling or breaking of DNA strands, which could lead to genetic abnormalities in the resulting cells. The other concepts, such as uncondensed DNA, the site of protein synthesis, or phases where cells grow, do not accurately describe the distinct role or structure of chromosomes during mitosis.