AP BIOLOGY

Detailed explanation-1: -In G2, after DNA replication in S phase, as cell enter mitotic prophase, each chromosome consists of a pair of identical sister chromatids, where each chromatid contains a linear DNA molecule that is identical to the joined sister. The sister chromatids are joined at their centromeres, as shown in the image below.

Detailed explanation-2: -Answer and Explanation: Before the mitotic phase, each chromosome present in a eukaryotic cell usually consists of similar structures, referred to as sister chromatids.

Detailed explanation-3: -Prophase: During prophase, the nuclear envelope of the cell (which is where the 92 sister chromatids are contained) begins to break down.

Detailed explanation-4: -The cell structure that joins two sister chromatids together during prophase is called the centromere. When the DNA of a chromosome is replicated two identical copies are formed. These identical copies are referred to as sister chromatids.

Detailed explanation-5: -At the beginning of prophase, the chromosomes are condensing to become visible microscopically. Each chromosome consists of two parallelsister chromatids, joined together at one point along their length at thecentromere. As chromosomes condense, the nucleolus disappears.