Recombination nodules are a part of the synaptonemic complex. It is the place where the crossing-over of homologous chromosomes occurs.
This occurs in the stage of Paquiteno, during Prophase I of Meiosis.
It is a protein structure that contains the enzymes needed to exchange genes (genetic information) between the chromatids of the two homologous chromosomes.
Enzymes such as endonucleases, DNA polymerase, DNA ligase and other essential for overcrossing. These enzymes fragment the double DNA helix, then these fragments are exchanged and the new double helix is fused again with the help of enzymes.
Biology, Oxford Education. Block II: Cell physiology. Page 194.
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