PATHOLOGY

Detailed explanation-1: -Prophase is the first stage in mitosis, occurring after the conclusion of the G2 portion of interphase. During prophase, the parent cell chromosomes-which were duplicated during S phase-condense and become thousands of times more compact than they were during interphase.

Detailed explanation-2: -Prophase is the first phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells. During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses.

Detailed explanation-3: -In prophase, the first step in mitosis, the nuclear envelope breaks down and chromosomes condense and become visible.

Detailed explanation-4: -The beginning of prophase is marked by the appearance of condensed chromosomes, each of which consists of two sister chromatids (the daughter DNA molecules produced in S phase). These newly replicated DNA molecules remain intertwined throughout S and G2, becoming untangled during the process of chromatin condensation.

Detailed explanation-5: -During prophase I, the pairs of homologous chromosomes come together to form a tetrad or bivalent, which contains four chromatids. Recombination can occur between any two chromatids within this tetrad structure. (The recombination process is discussed in greater detail later in this article.)