Cialis redirects here. For the Central Asian kingdom, see Karasahr. Tadalafil (INN) is a PDE5 inhibitor marketed in pill form for treating erectile dysfunction (ED) under the name Cialis see-AL-iss, and under the name Adcirca ad-SUR-kuh for the treatment of pulmonary arterial hypertension.
Quick Answer. The synapsis process occurs in the prophase I stage of meiosis. In synapsis, replicated homologous chromosomes link, which become known as a tetrad. Crossover between two pairs of tetrads can occur at any time. Continue Reading.
Two of the four cells will contain one recombinant chromosome. In eukaryotic cells, crossing over can also occur during mitosis. Somatic cells (non-sex cells) undergo mitosis to produce two distinct cells with identical genetic material.