Question

during which phase of meiosis does crossing over of chromosomes occur?
prophase i
metaphase i
anaphase i
telophase i

Explanation:

During prophase I of meiosis, homologous chromosomes pair up (synapsis) and form tetrads. It is during this stage that crossing - over (exchange of genetic material between non - sister chromatids of homologous chromosomes) occurs. Metaphase I is when homologous chromosomes align at the equatorial plate. Anaphase I is for the separation of homologous chromosomes. Telophase I is about the formation of two daughter nuclei with half the chromosome number (but still in a replicated state).

Answer:

prophase I