Question

Which among the following are cytogenetic events which occur during prophase I?

• A. Synapsis
• B. Crossing over
• C. Chiasma formation
• D. All of the above

Answer 1

The correct option is D All of the above

Meiosis comprises of two divisions meiosis I and meiosis II. The meiosis I occur in following stages prophase I, metaphase I, anaphase I and telophase I. Crossing over occurs during meiosis I. Homologous chromosomes pair during meiosis I, this is called as synapsis. The synapsis occurs between homologous chromosomes and facilitates crossing over. The exact point of crossing over is revealed by the formation of cross-shaped structures or chiasma formation during prophase I.

So, the correct answer is option D.