text: 'There are two general types of reproduction, asexual and sexual. Asexual reproduction involves only one parent, the offspring of which have chromosomes identical to those of the parent. Sexual reproduction generally involves two parents, each of which contributes half the chromosomes to the offspring. In the normal body cells of diploid organisms the chromosomes occur in pairs – one set being derived from the male parent and the other from the female parent. The two chromosomes of a pair are called homologous chromosomes. Thus each body cell in humans contains 46 chromosomes – 22 matched pairs from either parent, and one pair of sex chromosomes. In most animals, including humans, there are two kinds of sex chromosomes: X chromosomes, which are similar in size to the other chromosomes, and the smaller Y chromosomes. A combination of two X chromosomes gives a female, while one X and one Y chromosome gives a male'.