answers: pachytene stage of prophase I
context: During meiosis, the duplicated chromosomes (chromatids) in eukaryotic organisms are attached to each other in the centromere region and are thus paired. The maternal and paternal chromosomes then align alongside each other. During this time, recombination can take place via crossing over of sections of the paternal and maternal chromatids and leads to reciprocal recombination or non-reciprocal recombination. Unequal crossing over requires a measure of similarity between the sequences for misalignment to occur. The more similarity within the sequences, the more likely unequal crossing over will occur. One of the sequences is thus lost and replaced with the duplication of </s> Metaphase Metaphase (from the Greek μετά, "adjacent" and φάσις, "stage") is a stage of mitosis in the eukaryotic cell cycle in which chromosomes are at their second-most condensed and coiled stage (they are at their most condensed in anaphase). These chromosomes, carrying genetic information, align in the equator of the cell before being separated into each of the two daughter cells. Metaphase accounts for approximately 4% of the cell cycle's duration. Preceded by events in prometaphase and followed by anaphase, microtubules formed in prophase have already found and attached themselves to kinetochores in metaphase. In metaphase, the centromeres of the </s> Cohesin crosslinking occurs between the homologous chromosomes and helps them resist being pulled apart until anaphase. Genetic crossing-over, a type of recombination, occurs during the pachytene stage of prophase I. In addition, another type of recombination referred to as synthesis-dependent strand annealing (SDSA) frequently occurs. SDSA recombination involves information exchange between paired homologous chromatids, but not physical exchange. SDSA recombination does not cause crossing-over. In the process of crossing-over, genes are exchanged by the breaking and union of homologous portions of the chromosomes’ lengths. Structures called chiasmata are the site of the exchange. Chiasmata physically link the homologous chromosomes once
question: during which phase of meiosis do homologous chromosomes exchange segments