AP BIOLOGY

Detailed explanation-1: -During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses. The chromatin coils and becomes increasingly compact, resulting in the formation of visible chromosomes. Chromosomes are made of a single piece of DNA that is highly organized.

Detailed explanation-2: -DNA molecules first wrap around the histone proteins forming beads on string structure called nucleosomes. Nucleosomes further [inaudible] and condense/gather to form fibrous material which is called chromatin.

Detailed explanation-3: -During much of mitosis, DNA is wrapped and condensed into chromosomes (pictured). However, during this phase, DNA is uncondensed, and remains in the nucleus as a mass of chromatin, or a combination of DNA and proteins that the DNA wraps around.

Detailed explanation-4: -It follows the successful completion of S phase, during which the cell’s DNA is replicated. G2 phase ends with the onset of prophase, the first phase of mitosis in which the cell’s chromatin condenses into chromosomes.