Aetna CEO: Obamacare In A 'Death Spiral' Heading Into 2018. Aetna and Humana have called off their deal amid government concerns over competition. Here's a look back at six pivotal moments that led to this. Aetna and Humana have called off their deal amid government concerns over competition.
For the plant genus, see Synapsis (plant). Synapsis (also called syndesis) is the pairing of two homologous chromosomes that occurs during meiosis. It allows matching-up of homologous pairs prior to their segregation, and possible chromosomal crossover between them. Synapsis takes place during prophase I of meiosis.
In reality, prophase is the first stage of mitosis, and telophase is the last. Cytokinesis occurs only during mitosis and meiosis. Interphase is the stage of the cell cycle in which cells spend most (typically, more than 90%) of their time and perform their customary functions, including preparation for cell division.