Chiasmata are the points where homologous chromosomes exchange genetic material during meiosis, a type of cell division that produces gametes. This process occurs during prophase I, allowing for genetic recombination, which increases genetic diversity in offspring. The formation of chiasmata is crucial for proper chromosome segregation. Each chiasma represents a physical connection between the paired chromosomes, ensuring they align correctly during the subsequent stages of meiosis. This mechanism is essential for maintaining the correct number of chromosomes in the resulting gametes, which are vital for reproduction in organisms like humans and plants.