Final answer:
Chromosomes are uncondensed during interphase, which allows for gene activity. They condense only when a cell is preparing to divide to protect DNA and ensure proper segregation.
Step-by-step explanation:
When not undergoing cell division, chromosomes are found in an uncondensed state. In this state, also referred to as interphase, the DNA is packaged into a form known as chromatin, which resembles an unwound, jumbled bunch of threads and allows for genetic material to be accessible for transcription and replication. Specifically, during interphase, eukaryotic chromosomes display two distinct regions distinguishable by staining techniques: heterochromatin and euchromatin. Heterochromatin, the tightly packaged region that stains darkly, typically contains genes that are not active, while euchromatin, less densely packed and staining lighter, contains active genes that are being transcribed. As a cell prepares for division, these chromosomes condense to protect the DNA during this process, becoming visible under a microscope in structures known as metaphase chromosomes.