Answer:
increases genetic variation across gametes
occurs between homologous chromosomes
Explanation:
Crossing over is the exchange of chromosomal segments between homologous chromosomes during prophase I of meiosis. The process occur after the formation of bivalents/tetrads as a result of synapsed homologous chromosomes.
The exchange of chromosomal segments ensures that resulting meiotic gametes are genetically different from their parents, a phenomenon known as genetic variation.
Hence, the two statements out of the options that describe crossing over are:
- increases genetic variation across gametes
- occurs between homologous chromosomes
