These are the brain, heart, kidneys, liver, and lungs. The human brain is the body's control center, receiving and sending signals to other organs through the nervous system and through secreted hormones.
For the beetle genus, see Coprini. 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.
Replication occurs during interphase. 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. When this phase begins, the chromosomes have not yet replicated, but by the beginning of prophase replication is complete, so that each chromosome is composed of two sister chromatids.