Image caption Bridge is played by four players who form two partnerships and involves predicting the number of tricks each side will win. Bridge players who wanted the popular card game recognised as a sport have lost their High Court battle.
Meiosis occurs in diploid cells. The chromosomes duplicate once, and through two successive divisions, four haploid cells are produced, each with half the chromosome number of the parental cell. Meiosis occurs only in sexually reproducing organisms.
(See figure below, where meiosis I begins with a diploid (2n = 4) cell and ends with two haploid (n = 2) cells.) In humans (2n = 46), who have 23 pairs of chromosomes, the number of chromosomes is reduced by half at the end of meiosis I (n = 23). Prophase I.