Pachytene StageSpermatocytesSpermatogenesisMeiosisTestisSynaptonemal ComplexMeiotic Prophase IChromosome PairingSpermatogoniaSpermatozoaInfertility, MaleGerm CellsGeneticsSpermatidsDNA-Binding ProteinsProphaseSertoli CellsSeminiferous TubulesGenetics, PopulationSeminiferous EpitheliumCrossing Over, Genetic