What is "crossing over," and during which phase does it occur?

Question

A. Exchange of genetic material; occurs during Prophase I
B. Separation of sister chromatids; occurs during Metaphase II
C. Division of cytoplasm; occurs during Telophase I
D. DNA replication; occurs during Interphase

Answer 1

A. Exchange of genetic material; occurs during Prophase I

Crossing over is the process where homologous chromosomes exchange genetic material during meiosis, specifically during Prophase I. This contributes to genetic diversity in the resulting gametes.